Colorado State defensive back Henry Blackburn has faced intense criticism since he drew an unnecessary roughness penalty for a vicious late hit on Colorado standout Travis Hunter on Saturday.

Since the controversial play, Blackburn and his family have received death threats, CSU athletic director Joe Parker told ESPN’s Pete Thamel.

“We’re very concerned about our player’s safety, as Henry and his family have continued to receive these threats,” Parker told Thamel. “Henry never intended to put anyone in harm’s way on the football field. It’s not what we teach or coach. We hope that the irrational vitriol directed at Henry stops immediately.”

Blackburn’s and his mother’s cell phone numbers, along with his campus and home address were published online. Threats have been directed at Blackburn and his family via social media, text and phone.

Rams football coach Jay Norvell spoke about the threats directed at Blackburn at a Monday press conference.

“Our university is supporting him. The police department is supporting him, because of the seriousness of the threats that have come out of this,” Norvell said, via The Denver Post. “It’s just sad. It’s sad that that’s the state of the world we live in. I mean, it’s a football game. Let’s not make it more than that. We don’t want anybody to get hurt. We don’t coach that kind of football.”

Hunter is expected to be out for at least three weeks following the Buffaloes’ 43–35 double-overtime win in the rivalry game.