The entrance of UCLA. Photo: Wikimedia Commons.

Police in Boulder, Colorado on Tuesday arrested a former University of California-Los Angeles (UCLA) postdoctoral fellow for threatening to commit a mass shooting and issuing a racist and antisemitic manifesto.

“Upon reviewing parts of the manifesto, we identified thousands of references to violence, stating things such as killing, death, murder, shootings, bombs, schoolyard massacre in Boulder, and phrases like ‘burn and attack Boulder outside of the university,'” Boulder Police Chief Maris Herold said Tuesday during a press conference, after the arrest of 31-year-old Matthew Christopher Harris. “The male had attempted to buy an unknown handgun at a store located in Jefferson County on November 2. He was denied this purchase.”

According to a local ABC affiliate, Harris’ troubling behavior began during his employment at UCLA, where he was placed on leave in January 2021 for “predatory behavior” after sending pornography to students. That same month, he told his mother he planned to “hunt” and “put bullets in the skull” of a female University of California-Irvine professor he met while completing his dissertation in philosophy at Duke University. Harris and the professor did not have a significant relationship, said ABC 7, but he contacted her seeking career advice in September 2020, when he moved to Los Angeles.

“I wouldn’t be able to live with myself if I did nothing and someone got hurt,” Harris’ mother, from whom he was estranged for five years, told the professor in April 2021, warning her of the threat against her life.

UCLA successfully attained a workplace violence restraining order against Harris, effective until 2024, last June. Boulder Police said Tuesday that the protective order and another that forbade him to possess firearms likely prevented his purchasing one last November.

On Sunday, after midnight, Harris sent an email to students and staff at UCLA’s philosophy department that disparaged Jews, Asians, and other racial groups. The email also included a video, “UCLA PHILOSOPHY (MASS SHOOTING), that was uploaded to Harris’ YouTube account. According to the Los Angeles Times, it clipped together footage of a 2017 mass shooting in Las Vegas and scenes from “Zero Day,” a film based on the 1999 mass shooting at Columbine High School.

“Violence against Jews should happen,” he wrote to former colleagues. “Retaliation and retribution for what they have stolen is legitimate and a good thing.”

Other videos from Harris’ YouTube page, LA Times said, showed him creating a “list” of areas of the UCLA campus that he planned to target.

Responding to Harris’ email UCLA cancelled classes on Tuesday “out of an abundance of caution.” The next morning, around 7:30 a.m., the Boulder Regional SWAT team was dispatched around the perimeter of Harris’ apartment complex while Boulder Police evacuated schools and businesses in the area and residents near his home were ordered to shelter-in-place. After a three hour standoff, he peacefully surrendered and was taken into custody, where he remains awaiting federal charges.

“The Boulder Police Department took these threats and what they read in that manifesto very seriously, and acted immediately,” Boulder County District Attorney Michael Dougherty said at Tuesday’s press conference. “We have a safe and peaceful resolution today, and I want to acknowledge that what they did and how they went about it is why there were no injuries and no casualties associated with this event.”

Police Chief Herold credited Harris’ timely arrest to the county’s communication with federal agencies, including the FBI.

“The importance of having collaboration at the federal, state, and local level was critical to the swift resolution of this incident this morning,” 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.”

After Harris’ arrest, UCLA Assistant Vice Chancellor for Student Development Suzanne L. Seplow and Health and Assistant Vice Chancellor for Campus Life Michael Deluca wrote to the campus community saying they were “greatly relieved.”

“The threats made yesterday were frightening for many of us and caused our community to feel vulnerable at an already challenging time,” they said in a message obtained by LA Times. “These are unsettling times and your well-being is a top priority, so please do not hesitate to reach out for help if you need it.”