Campus Alert Archive
UCSD

Knife displayed after a bookstore disturbance

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CAweaponstimely warninghigh confidence
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Under Investigation

UC San Diego Police issued a Clery timely warning after a weapons-law violation at the UCSD Bookstore. Police were notified at 2:39 p.m. December 19; the incident was about 12:05 p.m. A suspect causing a disturbance was asked to leave, displayed a knife with an approximately 3-inch blade, and was last seen eastbound on Lyman Lane toward the Student Services Center.

Alerts
1
Response
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Killed
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Injured
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Institution
University of California, San Diego
Public R1 · CA
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Triton Alert
Official alert policy
Read when and how UCSD says it will use Triton Alert: summarized, quoted, and analyzed.
Documented Timeline

Alert Sequence

1 message in sequence · 1 verified verbatim

Confirmed wording is transcribed character-for-character from a primary source. Use Verify this quote under each message to open that source in a new tab and compare the text yourself.

INITIAL ALERTEmail
Verified verbatim2366 chars
UC SAN DIEGO POLICE DEPARTMENT December 19, 2025 ALL ACADEMICS, STAFF, AND STUDENTS AT UC SAN DIEGO Timely Warning – Weapons Law Violation On December 19th, 2025, at 2:39 PM, the UC San Diego Police Department received a report of a weapons law violation that occurred at the UCSD Bookstore at approximately 12:05 PM. The reporting party stated that the suspect was causing a disturbance in the bookstore and was asked to leave. As the suspect left the location, he displayed a knife with an approximate 3” blade and walked out of the bookstore. The suspect was last seen eastbound on Lyman Lane. towards the Student Services Center. The suspect is described by the victim as a male adult, approximately 20-30 years old, with short black hair, wearing a black hooded sweatshirt with a Nike Logo, dark pants, dark gray shoes, and a gray backpack. At this time, the suspect is not in custody. The report is currently under investigation by the UC San Diego Police Department. If you have information that could be helpful in this investigation, please call the UC San Diego Police Department at (858) 534-4357 or submit an online tip at https://police.ucsd.edu/services/anonymous.html. The remainder of this message provides general information about preventing and reporting a weapons law violation and is not necessarily related to this incident. Report suspicious activity immediately to the UC San Diego Police Department by calling or texting 9-1-1. Your safety is most important. If you are confronted with someone who says they have a gun, knife or other weapon, believe them. Try to maintain a calm demeanor. Don’t make sudden moves or try to apprehend the criminal yourself. Use the UC San Diego Safety Escort Program. Call (858) 534-WALK, available daily from dusk to dawn. Whenever possible, travel well-lit, busy routes. Avoid walking or parking in shadowed areas. Have your keys in your hand as you approach your door. Know the location of Campus Emergency Telephones on routes to and from campus destinations. What is this Notice? This notice is being provided to you to comply with the Jeanne Clery Campus Safety Act. Timely Warnings are intended to prevent similar crimes and to provide information that will assist community members in protecting themselves. University of California San Diego, 9500 Gilman Drive, La Jolla, CA, 92093
Verify this quote
UC San Diego Campus Notices wiki: Timely Warning Weapons Law Violation 12-19-2025 (UCSD Bookstore)ucsdcampusnotices.atlassian.netfind archived copies
Dual independent Confluence REST fetch 2026-08-24. CDATA html sha256 64cde25acdea92616c1ba70d9f382bfb545ec5478b8110f69a70b602f383652f. Flattened from the embedded UCPD email body (this notice is a Confluence HTML macro, not an htmlCode JSON embed). En dash, curly apostrophe, and 3-inch rdquo preserved. Official 'Lyman Lane. towards' period preserved. SPN save-sync HTTP 302.
Distinct from 2026-01-04-uc-san-diego-seventh-marshall-bedroom-burglaries (later date, burglary/SIP series) and from the 2025-12-15 burglary TW still queued on the listing.
Message elements

How the first alert is built

To check this alert, SuperGrok Heavy 4.5 (an AI) read it in full 25 separate times, independently. Each read decided whether the message answers each of the six questions and gave a short reason. A final reviewer then weighed all 25 and wrote the plain-English verdict you see when you open a row. The score (for example 22/25) is how many reads agreed; the 25 individual reads are tucked underneath if you want to check them.

UC SAN DIEGO POLICE DEPARTMENT December 19, 2025 ALL ACADEMICS, STAFF, AND STUDENTS AT UC SAN DIEGO Timely Warning – Weapons Law Violation On December 19th, 2025, at 2:39 PM, the UC San Diego Police Department received a report of a weapons law violation that occurred at the UCSD Bookstore at approximately 12:05 PM. The reporting party stated that the suspect was causing a disturbance in the bookstore and was asked to leave. As the suspect left the location, he displayed a knife with an approximate 3” blade and walked out of the bookstore. The suspect was last seen eastbound on Lyman Lane. towards the Student Services Center. The suspect is described by the victim as a male adult, approximately 20-30 years old, with short black hair, wearing a black hooded sweatshirt with a Nike Logo, dark pants, dark gray shoes, and a gray backpack. At this time, the suspect is not in custody. The report is currently under investigation by the UC San Diego Police Department. If you have information that could be helpful in this investigation, please call the UC San Diego Police Department at (858) 534-4357 or submit an online tip at https://police.ucsd.edu/services/anonymous.html. The remainder of this message provides general information about preventing and reporting a weapons law violation and is not necessarily related to this incident. Report suspicious activity immediately to the UC San Diego Police Department by calling or texting 9-1-1. Your safety is most important. If you are confronted with someone who says they have a gun, knife or other weapon, believe them. Try to maintain a calm demeanor. Don’t make sudden moves or try to apprehend the criminal yourself. Use the UC San Diego Safety Escort Program. Call (858) 534-WALK, available daily from dusk to dawn. Whenever possible, travel well-lit, busy routes. Avoid walking or parking in shadowed areas. Have your keys in your hand as you approach your door. Know the location of Campus Emergency Telephones on routes to and from campus destinations. What is this Notice? This notice is being provided to you to comply with the Jeanne Clery Campus Safety Act. Timely Warnings are intended to prevent similar crimes and to provide information that will assist community members in protecting themselves. University of California San Diego, 9500 Gilman Drive, La Jolla, CA, 92093

  • Sourcepresent25/25

    Final assessment

    UC SAN DIEGO POLICE DEPARTMENT is the branded sender.

    Who is sending the alert and who is responding. People act faster on a message from a clearly identifiable, credible sender, such as a named department, the police, or a branded alert system, than on an anonymous notice. A branded signature counts.

    See all 25 individual reads
    1. present: The deciding words are "UC SAN DIEGO POLICE DEPARTMENT", so this element is present.
    2. present: This read treats "UC SAN DIEGO POLICE DEPARTMENT" as enough to mark the element present.
    3. present: Quoted evidence "UC SAN DIEGO POLICE DEPARTMENT" is the specific language that carries the element.
    4. present: I mark present because the alert includes "UC SAN DIEGO POLICE DEPARTMENT".
    5. present: Presence follows from the phrase "UC SAN DIEGO POLICE DEPARTMENT" in the body.
    6. present: The message supplies "UC SAN DIEGO POLICE DEPARTMENT", which satisfies the element on this pass.
    7. present: On this independent read, "UC SAN DIEGO POLICE DEPARTMENT" is the hook that makes the element present.
    8. present: Element is present: the text itself contains "UC SAN DIEGO POLICE DEPARTMENT".
    9. present: A first-time reader would see "UC SAN DIEGO POLICE DEPARTMENT" and know the element is there.
    10. present: Coding present from the explicit wording "UC SAN DIEGO POLICE DEPARTMENT".
    11. present: The body names it with "UC SAN DIEGO POLICE DEPARTMENT", so the vote is present.
    12. present: This pass votes present on the strength of "UC SAN DIEGO POLICE DEPARTMENT".
    13. present: Because the alert says "UC SAN DIEGO POLICE DEPARTMENT", the element is not missing.
    14. present: The quoted span "UC SAN DIEGO POLICE DEPARTMENT" is sufficient and does not need outside knowledge.
    15. present: Present: "UC SAN DIEGO POLICE DEPARTMENT" is in the transmitted text.
    16. present: I am scoring present after locating "UC SAN DIEGO POLICE DEPARTMENT" in the message.
    17. present: The element is carried by "UC SAN DIEGO POLICE DEPARTMENT" rather than by implication alone.
    18. present: Direct language "UC SAN DIEGO POLICE DEPARTMENT" is what this pass uses for a present vote.
    19. present: Nothing in the rest of the text undoes "UC SAN DIEGO POLICE DEPARTMENT" as the present cue.
    20. present: This reviewer finds "UC SAN DIEGO POLICE DEPARTMENT" and therefore records present.
    21. present: The alert is not silent here: it has "UC SAN DIEGO POLICE DEPARTMENT".
    22. present: Present vote rests on the visible words "UC SAN DIEGO POLICE DEPARTMENT".
    23. present: From the four corners of the message, "UC SAN DIEGO POLICE DEPARTMENT" establishes the element.
    24. present: I quote "UC SAN DIEGO POLICE DEPARTMENT" as the sole basis for present on this pass.
    25. present: Independent judgment: "UC SAN DIEGO POLICE DEPARTMENT" is on the page, so present.
  • Hazardpresent25/25

    Final assessment

    weapons law violation and displayed a knife name a specific hazard.

    What the threat actually is. A complete warning names the specific danger, such as a shooter, a fire, a tornado, or a gas leak, rather than a vague emergency, because people decide what to do based on what they are facing.

    See all 25 individual reads
    1. present: The deciding words are "weapons law violation", so this element is present.
    2. present: This read treats "weapons law violation" as enough to mark the element present.
    3. present: Quoted evidence "weapons law violation" is the specific language that carries the element.
    4. present: I mark present because the alert includes "weapons law violation".
    5. present: Presence follows from the phrase "weapons law violation" in the body.
    6. present: The message supplies "weapons law violation", which satisfies the element on this pass.
    7. present: On this independent read, "weapons law violation" is the hook that makes the element present.
    8. present: Element is present: the text itself contains "weapons law violation".
    9. present: A first-time reader would see "weapons law violation" and know the element is there.
    10. present: Coding present from the explicit wording "weapons law violation".
    11. present: The body names it with "weapons law violation", so the vote is present.
    12. present: This pass votes present on the strength of "weapons law violation".
    13. present: Because the alert says "weapons law violation", the element is not missing.
    14. present: The quoted span "weapons law violation" is sufficient and does not need outside knowledge.
    15. present: Present: "weapons law violation" is in the transmitted text.
    16. present: I am scoring present after locating "weapons law violation" in the message.
    17. present: The element is carried by "weapons law violation" rather than by implication alone.
    18. present: Direct language "weapons law violation" is what this pass uses for a present vote.
    19. present: Nothing in the rest of the text undoes "weapons law violation" as the present cue.
    20. present: This reviewer finds "weapons law violation" and therefore records present.
    21. present: The alert is not silent here: it has "weapons law violation".
    22. present: Present vote rests on the visible words "weapons law violation".
    23. present: From the four corners of the message, "weapons law violation" establishes the element.
    24. present: I quote "weapons law violation" as the sole basis for present on this pass.
    25. present: Independent judgment: "weapons law violation" is on the page, so present.
  • Locationpresent25/25

    Final assessment

    UCSD Bookstore, Lyman Lane, and the Student Services Center are named places.

    Where the threat is. Saying whether danger is in a specific building, a part of campus, or area-wide lets people judge their own proximity and choose a safe direction. Without a where, a warning is hard to act on precisely.

    See all 25 individual reads
    1. present: The deciding words are "UCSD Bookstore", so this element is present.
    2. present: This read treats "UCSD Bookstore" as enough to mark the element present.
    3. present: Quoted evidence "UCSD Bookstore" is the specific language that carries the element.
    4. present: I mark present because the alert includes "UCSD Bookstore".
    5. present: Presence follows from the phrase "UCSD Bookstore" in the body.
    6. present: The message supplies "UCSD Bookstore", which satisfies the element on this pass.
    7. present: On this independent read, "UCSD Bookstore" is the hook that makes the element present.
    8. present: Element is present: the text itself contains "UCSD Bookstore".
    9. present: A first-time reader would see "UCSD Bookstore" and know the element is there.
    10. present: Coding present from the explicit wording "UCSD Bookstore".
    11. present: The body names it with "UCSD Bookstore", so the vote is present.
    12. present: This pass votes present on the strength of "UCSD Bookstore".
    13. present: Because the alert says "UCSD Bookstore", the element is not missing.
    14. present: The quoted span "UCSD Bookstore" is sufficient and does not need outside knowledge.
    15. present: Present: "UCSD Bookstore" is in the transmitted text.
    16. present: I am scoring present after locating "UCSD Bookstore" in the message.
    17. present: The element is carried by "UCSD Bookstore" rather than by implication alone.
    18. present: Direct language "UCSD Bookstore" is what this pass uses for a present vote.
    19. present: Nothing in the rest of the text undoes "UCSD Bookstore" as the present cue.
    20. present: This reviewer finds "UCSD Bookstore" and therefore records present.
    21. present: The alert is not silent here: it has "UCSD Bookstore".
    22. present: Present vote rests on the visible words "UCSD Bookstore".
    23. present: From the four corners of the message, "UCSD Bookstore" establishes the element.
    24. present: I quote "UCSD Bookstore" as the sole basis for present on this pass.
    25. present: Independent judgment: "UCSD Bookstore" is on the page, so present.
  • Guidancepresent25/25

    Final assessment

    Recipients are told to report suspicious activity by calling or texting 9-1-1 and not to apprehend the person themselves.

    The protective action to take. A clear, specific instruction, such as shelter in place, evacuate, avoid the area, or run-hide-fight, drives faster and more correct protective behavior than describing the threat alone.

    See all 25 individual reads
    1. present: The deciding words are "calling or texting 9-1-1", so this element is present.
    2. present: This read treats "calling or texting 9-1-1" as enough to mark the element present.
    3. present: Quoted evidence "calling or texting 9-1-1" is the specific language that carries the element.
    4. present: I mark present because the alert includes "calling or texting 9-1-1".
    5. present: Presence follows from the phrase "calling or texting 9-1-1" in the body.
    6. present: The message supplies "calling or texting 9-1-1", which satisfies the element on this pass.
    7. present: On this independent read, "calling or texting 9-1-1" is the hook that makes the element present.
    8. present: Element is present: the text itself contains "calling or texting 9-1-1".
    9. present: A first-time reader would see "calling or texting 9-1-1" and know the element is there.
    10. present: Coding present from the explicit wording "calling or texting 9-1-1".
    11. present: The body names it with "calling or texting 9-1-1", so the vote is present.
    12. present: This pass votes present on the strength of "calling or texting 9-1-1".
    13. present: Because the alert says "calling or texting 9-1-1", the element is not missing.
    14. present: The quoted span "calling or texting 9-1-1" is sufficient and does not need outside knowledge.
    15. present: Present: "calling or texting 9-1-1" is in the transmitted text.
    16. present: I am scoring present after locating "calling or texting 9-1-1" in the message.
    17. present: The element is carried by "calling or texting 9-1-1" rather than by implication alone.
    18. present: Direct language "calling or texting 9-1-1" is what this pass uses for a present vote.
    19. present: Nothing in the rest of the text undoes "calling or texting 9-1-1" as the present cue.
    20. present: This reviewer finds "calling or texting 9-1-1" and therefore records present.
    21. present: The alert is not silent here: it has "calling or texting 9-1-1".
    22. present: Present vote rests on the visible words "calling or texting 9-1-1".
    23. present: From the four corners of the message, "calling or texting 9-1-1" establishes the element.
    24. present: I quote "calling or texting 9-1-1" as the sole basis for present on this pass.
    25. present: Independent judgment: "calling or texting 9-1-1" is on the page, so present.
  • Timepresent25/25

    Final assessment

    December 19th, 2025, at 2:39 PM is an explicit clock time and date.

    When the message applies. A timestamp, the word now or immediately, or a phrase like until further notice tells the reader whether the danger is current and how quickly to act.

    See all 25 individual reads
    1. present: The deciding words are "December 19th, 2025, at 2:39 PM", so this element is present.
    2. present: This read treats "December 19th, 2025, at 2:39 PM" as enough to mark the element present.
    3. present: Quoted evidence "December 19th, 2025, at 2:39 PM" is the specific language that carries the element.
    4. present: I mark present because the alert includes "December 19th, 2025, at 2:39 PM".
    5. present: Presence follows from the phrase "December 19th, 2025, at 2:39 PM" in the body.
    6. present: The message supplies "December 19th, 2025, at 2:39 PM", which satisfies the element on this pass.
    7. present: On this independent read, "December 19th, 2025, at 2:39 PM" is the hook that makes the element present.
    8. present: Element is present: the text itself contains "December 19th, 2025, at 2:39 PM".
    9. present: A first-time reader would see "December 19th, 2025, at 2:39 PM" and know the element is there.
    10. present: Coding present from the explicit wording "December 19th, 2025, at 2:39 PM".
    11. present: The body names it with "December 19th, 2025, at 2:39 PM", so the vote is present.
    12. present: This pass votes present on the strength of "December 19th, 2025, at 2:39 PM".
    13. present: Because the alert says "December 19th, 2025, at 2:39 PM", the element is not missing.
    14. present: The quoted span "December 19th, 2025, at 2:39 PM" is sufficient and does not need outside knowledge.
    15. present: Present: "December 19th, 2025, at 2:39 PM" is in the transmitted text.
    16. present: I am scoring present after locating "December 19th, 2025, at 2:39 PM" in the message.
    17. present: The element is carried by "December 19th, 2025, at 2:39 PM" rather than by implication alone.
    18. present: Direct language "December 19th, 2025, at 2:39 PM" is what this pass uses for a present vote.
    19. present: Nothing in the rest of the text undoes "December 19th, 2025, at 2:39 PM" as the present cue.
    20. present: This reviewer finds "December 19th, 2025, at 2:39 PM" and therefore records present.
    21. present: The alert is not silent here: it has "December 19th, 2025, at 2:39 PM".
    22. present: Present vote rests on the visible words "December 19th, 2025, at 2:39 PM".
    23. present: From the four corners of the message, "December 19th, 2025, at 2:39 PM" establishes the element.
    24. present: I quote "December 19th, 2025, at 2:39 PM" as the sole basis for present on this pass.
    25. present: Independent judgment: "December 19th, 2025, at 2:39 PM" is on the page, so present.
  • Impactpresent20/25

    Final assessment

    Your safety is most important plus the knife-confrontation remainder states severity. Five passes coded absent because the incident graf reports no injury.

    What the hazard could do to the people in its path. Beyond naming the threat, a complete warning conveys its potential consequences or severity, such as that a tornado can level buildings or that a leak could be explosive, so recipients grasp how much danger they are in. Research on warning message content finds that a concrete impact statement helps people personalize their risk and act sooner.

    See all 25 individual reads
    1. present: The deciding words are "Your safety is most important", so this element is present.
    2. present: This read treats "Your safety is most important" as enough to mark the element present.
    3. present: Quoted evidence "Your safety is most important" is the specific language that carries the element.
    4. present: I mark present because the alert includes "Your safety is most important".
    5. absent: The incident graf names the weapons law violation but does not state injury, death, or other consequence, so impact is absent.
    6. present: The message supplies "Your safety is most important", which satisfies the element on this pass.
    7. present: On this independent read, "Your safety is most important" is the hook that makes the element present.
    8. present: Element is present: the text itself contains "Your safety is most important".
    9. present: A first-time reader would see "Your safety is most important" and know the element is there.
    10. absent: No phrase such as life-threatening or could be deadly appears in the incident narrative; I vote impact absent.
    11. present: The body names it with "Your safety is most important", so the vote is present.
    12. present: This pass votes present on the strength of "Your safety is most important".
    13. present: Because the alert says "Your safety is most important", the element is not missing.
    14. present: The quoted span "Your safety is most important" is sufficient and does not need outside knowledge.
    15. absent: Displaying a knife names the hazard; it does not by itself tell recipients what harm would follow, so impact is missing.
    16. present: I am scoring present after locating "Your safety is most important" in the message.
    17. present: The element is carried by "Your safety is most important" rather than by implication alone.
    18. present: Direct language "Your safety is most important" is what this pass uses for a present vote.
    19. present: Nothing in the rest of the text undoes "Your safety is most important" as the present cue.
    20. absent: I do not treat Your safety is most important as a stated consequence of this bookstore incident, so impact is absent.
    21. present: The alert is not silent here: it has "Your safety is most important".
    22. present: Present vote rests on the visible words "Your safety is most important".
    23. present: From the four corners of the message, "Your safety is most important" establishes the element.
    24. present: I quote "Your safety is most important" as the sole basis for present on this pass.
    25. absent: This pass codes impact absent because the transmitted crime description reports no victim injury.

Coded by SuperGrok Heavy 4.5

Systematic AI judgments with visible reasoning, not human-validated codings.

About this analysis
Context

Background

UC San Diego Police posted the notice on the Campus Notices wiki, linked from police.ucsd.edu/alerts/warnings.html.
Analysis

Key Findings

Suspect asked to leave the bookstore displayed a knife with an approximately 3-inch blade and walked eastbound on Lyman Lane toward the Student Services Center.
Described as a male adult, about 20-30, short black hair, black Nike hoodie, dark pants, dark gray shoes, gray backpack. Not in custody.
Outcome
No custody. Investigation open.
Provenance

Sources

Every claim on this page is meant to be checkable. Open the links below (and the Verify this quote control under each confirmed alert) to read the original university, news, or archive page yourself. Hostnames are shown so you can see where you are going; archived copies survive when live pages move or disappear. See also our methodology.

  1. Official
    Timely Warning – Weapons Law Violation - 12-19-2025
    ucsdcampusnotices.atlassian.net
    archived copy
Cite this case

Campus Alert Archive. "University of California, San Diego: Knife displayed after a bookstore disturbance." Incident of December 19, 2025. Added August 2026. https://campusalertarchive.com/case/uc-san-diego-bookstore-knife-display-2025-12-19/

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Alert text quoted on this page remains the work of the issuing institution; the archive is a secondary source.

Tags
public-r1californiaucsdweaponstimely-warning2025Under Investigation
Added August 2026Updated August 2026Via ingestion