Tyler Robinson, 22, accused of killing right-wing commentator Charlie Kirk, is set to appear in a Utah court Tuesday to face charges that may include capital murder.

Prosecutors and federal officials are still investigating whether Robinson acted alone or as part of a wider conspiracy, with possible hate crime charges pending.

FBI officials say DNA evidence links him to the rifle used, and text messages suggest he planned the shooting, The Guardian has reported.

Authorities also cited signs of an “obsession” with Kirk. Utah’s governor has vowed to pursue the death penalty, though prosecutors say that decision will come later as evidence is still being gathered.