BOULDER, Colo. — A man who sent a lengthy manifesto containing "thousands" of references to violence, including some targeting the Boulder area, was taken into custody Tuesday morning in the city after he was tracked there by authorities in California, Boulder's police chief said.
"The level of violence that we saw in the manifesto was obviously so alarming," said Chief Maris Herold, adding that they were still combing through its nearly 800 pages.
"But I can tell you it was very violent. It was very disturbing. There was definitely references to Boulder in the manifesto, and a university setting and a schoolyard setting."
The man identified as Matthew Christopher Harris was arrested shortly after 11 a.m. and the home where he lived is still being searched by law enforcement.
Harris was initially being held on state charges. The 20th Judicial District Attorney's Office said Tuesday night that federal charges are now pending against him. He is being transferred to federal custody, the office said.
The video below shows Harris being taken into custody.
Harris is a former lecturer at UCLA, the Associated Press reports.
On Monday, an email containing Harris' manifesto was sent to some people within the UCLA community. Upon learning of the email, authorities there tracked Harris to Colorado and notified BPD late Monday.
"Upon reviewing parts of the manifesto, we identified thousands of references to violence, " said Herold. "Stating things such as killing, death, murder, shootings, bombs – schoolyard massacre and phrases like burn and attack Boulder outside of the university."
The Associated Press reports he had previously sent messages saying he would “hunt” and kill a professor.
Court records show that Harris sent his mother several emails last year in which he threatened a female professor at the University of California Irvine.
Harris' mother then forwarded the emails to the school system to warn them.
In one email from January of last year, Harris told his mother, "Just so you know. I will probably be moving closer to Irvine's campus so that I can hunt this b---- down and put bullets in her skull. My psychiatrist said good luck and told me l have schizophrenia."
When she forwarded the emails, Harris' mother wrote, "I'm sorry to drop all of this on you out of the blue. I only know that I wouldn't be able to live with myself if I did nothing and someone got hurt.
The Boulder regional SWAT was activated just before 8 a.m. Tuesday as officers attempted to contact Harris in the 900 block of Broadway.
The Boulder Valley School District said around 8:10 a.m. that University Hill Elementary was placed on a secure perimeter but eventually students were moved to the Boulder Valley School District Education Center to be picked up.
Police said nearby University of Colorado Boulder fraternity and sorority homes were evacuated and shelter-in-place orders were sent to about 65 homes in the immediate area. Shortly before 1 p.m., those orders were lifted.
"We do believe that he had a connection here in Boulder but we are just not sure of the magnitude of the relationships here at this time," said Herold.
Prior to the incident Tuesday morning, Herold said that Harris had attempted to buy a handgun from a store located in Jefferson County. He made that attempt on Nov. 2 but was denied and was unable to obtain a weapon, she said.
"Based on a protection order that was issued in the state of California, there was a national database that included a provision that he was not allowed to purchase or possess a firearm," said Boulder District Attorney Michael Dougherty.
While it's still early in the investigation, they believe that is what prevented Harris from successfully purchasing the gun in November.
Herold also said BPD had prior contact with Harris around October but no criminal charges resulted from that contact.
Also, according to the NBC affiliate in Los Angeles, LAPD contacted Harris in the spring of last year for a mental health evaluation. The result of that contact is not known at this point.
All in-person Tuesday classes were canceled at UCLA after Harris was accused of making threats against the campus and the department members, according to the Los Angeles NBC station. In a statement posted on Twitter, UCLA said it was "greatly relieved" to share that the suspect who made threats was taken into custody by law enforcement in Colorado.
Harris is now in federal custody in Colorado awaiting charges.
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