The man arrested on suspicion of murdering American far-right activist Charlie Kirk confessed to the killing in a text message he sent to his roommate, prosecutors said.

The prosecutor added that the suspect has been charged with seven counts.

Tyler Robinson, 22, left a note under his computer keyboard for his roommate and girlfriend, Utah County District Attorney Jeffrey Gray said.

He added that the person he shared a room with was his girlfriend.

According to Gray, the note said, "I had the opportunity to kill Charlie Kirk and I'm going to do it."

Prosecutors shared text messages between the two friends, saying in one message that the defendant said, "I had enough of the hate," so he killed him.

The suspect is being held without bail in the Utah County Jail.