UCLA canceled its campus activities and classes, Tuesday, after an alleged mass shooting threat from a former instructor.

The alleged threat came in the form of an email, where suspect Matthew Christopher Harris, 31, sent an 800-page manifesto to UCLA community members on Monday, titled “Death Sentences.”

Harris was arrested in Boulder, Colorado after the UCLA Police Dept. notified Boulder PD about his suspected whereabouts. He is currently being held on Colorado state charges, with the U.S. Attorney’s office being contacted since threats were made across state lines into California.

Boulder PD revealed portions of the manifesto which incorporated harm to the Boulder community, with passages such as, “burn and attack Boulder outside by the university.”

Boulder SWAT was called to his residence on Tuesday morning, with police evacuating nearby schools, businesses and residents.

After obtaining a search warrant, a crisis response team spoke with Harris on the phone, with his arrest coming around 11:07 a.m. MST.

“The importance of having collaboration at the federal, state and local levels was critical to the swift resolution of this incident this morning,” Boulder Police Chief Maris Herold said. “The incident today is yet another reminder of the ongoing need for strong relationships with our federal law enforcement partners to protect the Boulder community.”

At around 6:49 a.m., Tuesday, UCLA confirmed that Harris was not in California, but continued with its remote learning plans for the day.

“I am greatly relieved to share that law enforcement officers in Colorado have taken into custody the individual who made threats against some members of our UCLA community yesterday,” UCLA said in a statement. “The threats made yesterday were frightening for many of us and caused our community to feel vulnerable at an already challenging time.”

LA Weekly