UC Riverside student Anton Shirokov, 29, has been taken into custody after admitting to posting a threat of violence on the popular social media app Yik Yak last night between the hours of 9 p.m. and 10 p.m.

According to a widely shared post, the threat read “UCR shooting spree coming! Mark my words, you cattle,” but Assistant Vice Chancellor for Strategic Communications James Grant was unable to confirm that this was the text of the threat.

Shirokov turned himself in to police at 1:40 a.m. and admitted that he had posted it as a joke after several concerned students reported the threat. He removed the threat shortly after posting it.

His apartment was searched, and police found brass knuckles, which are illegal to own in California. He is being brought up on weapons charges relating to the knuckles, but the district attorney is currently negotiating what other charges to file.

According to Grant, Yik Yak is cooperating with police, but Grant was unable to provide more details about the progress of the investigation.

Many students were shaken up by the post in light of the shootings that have occurred in the past few years, including the Isla Vista shooting that took place near UC Santa Barbara in May of last year.

“In the back of my mind, I was thinking maybe it was a joke, but it’s still kind of scary,” said first-year biology major Angela Burmayan, who learned of the threat via a text message from a friend.

“I’m legit scared to go to school, I’m always scared that something like this will happen,” read one Yik Yak post.

“It’s got a bunch of people, including me, afraid to go to my own school,” read another.

Shirokov could not be reached for comment.