A student at Glen A. Wilson High School in Hacienda Heights, California was arrested Friday on suspicion of making criminal threats against students via the Wikipedia article on the school. The threats were first noticed by Wikipedia administrators, who notified local police of the threats. As a precautionary measure, the school was closed on Friday.

The student was arrested on Friday at approximately 11:30 a.m. PDT, according to a statement from Hacienda La Puente Unified School District Department of Police and Safety Chief Al Vasquez made to Pasadena Star-News. Described as a male minor by Hacienda La Puente Unified School District police, he confessed to making threats against students at the high school via a post to the Wikipedia article about the school. The student made "a complete confession", said Superintendent Barbara Nakaoka to the Whittier Daily News. She also said that "Our police officers are continuing to work with the Los Angeles County Sheriff's Department to determine the validity of the threat."

Sheriff's Lt. Victor Sotelo told the Whittier Daily News that the police filed a "detain petition" which recommends that the minor not be released to his parents, and be held at juvenile hall. The California Youth Authority will decide what happens to the boy next. Lt. Sotelo said that law enforcement searched the student's home and recovered evidence.

Dreadstar notified others about the threat in a post to the Administrators' incident noticeboard on Wednesday April 16, at 8:58 p.m. PST, saying: "Can someone review this threat to see if any action should be taken?" Administrator John Reaves contacted local police in Los Angeles at 9:40 p.m. PST, and was in contact with a detective in order to work with the Internet service provider to find more information on the IP address that made the threat.

Los Angeles County sheriff's officials contacted Hacienda La Puente Unified School District police and informed them of a threat made against Glen A. Wilson High School posted to its article on Wikipedia. Two threats were made via posts to the Wikipedia article: an initial post, and a subsequent threat when the first post was removed by a Wikipedia editor.

The Los Angeles Times quoted a portion of the threats: "This is a warning. Do not remove this from this page. On Friday, April 18, 2008, there will be a shooting at this school. Current list of victims to be shot on this day: ...", said the initial post. The post named a hit list of specific students, and also said a shooting would affect "a good majority of the badminton team and almost every single fob." (NB: Fob). The poster threatened: "Take this text down and it will guarantee their death..."

While police were in the process of contacting the specific students named in the threat, a second threat was made on Wikipedia: "You removed my last edit. I gave you a fair warning. Now the people listed in my previous edit will be victims in the Glen A. Wilson Shooting to occur this Friday. Your lack of attention to the seriousness of my warning will now be the reason as to why you will receive all fault of this event." The threats were later removed from the edit history of the article by Wikipedia administrator Persian Poet Gal, at 9:08 p.m. PDT on Friday, after the student had been arrested.

All students' backpacks were searched before classes began Thursday. At the time Hacienda La Puente Unified School District police told the Pasadena Star-News that the random checks were a precautionary measure related to the upcoming anniversary of the Columbine High School massacre, which took place April 20, 1999. Eric Harris and Dylan Klebold killed 12 students and a teacher and wounded many others in Columbine High School in Colorado before committing suicide.

Classes were canceled at the high school on Friday. In a statement to the Los Angeles Times, Chief Al Vasquez explained the decision to close the school: "If I had not thought it was credible, we would not have closed the school. I mean, not one but two threats." Chief Vasquez said that the high school would be open for classes on Monday.

• "Wikipedia:Administrators' noticeboard/Incidents - Threat", Wikipedia, April 19, 2008.
• Sun Yunlong. "School student arrested for making online threats", Xinhua News Agency, April 19, 2008.
• Molly Hennessy-Fiske. "Hacienda Heights high school student arrested in online threats", Los Angeles Times, April 19, 2008.
• Brian Day. "Student arrested in suspected Web threats", Whittier Daily News, April 18, 2008.
• "Student arrested in high school threats", Pasadena Star-News, April 18, 2008.
• "Increased security at Wilson High", Pasadena Star-News, April 17, 2008.