Utah Governor Spencer Cox said Tyler Robinson, 22, the suspect in the killing of conservative activist Charlie Kirk, is refusing to cooperate with investigators and has not confessed.

Robinson was arrested 33 hours after Kirk was shot dead while speaking at a Turning Point USA event at Utah Valley University.

Authorities are still working to establish a motive, with Robinson’s friends and partner providing information to police, the BBC has reported.

Robinson faces charges including aggravated murder and is being held without bail, while Kirk’s death has sparked calls for unity and tributes ahead of a large memorial service in Arizona.