Charlie Kirk was allegedly killed with an older model hunting rifle, which was found in the woods near the scene of Wednesday's shooting at the University of Utah.
The rifle was reportedly wrapped in a towel with a shell casing in the barrel. Three unfired bullets with engraved inscriptions were also found.
According to investigators, the shot was fired from a long-range rifle from the roof of a building about 200 meters from the crime scene.
At the time of the attack, Kirk was speaking to an audience of about 3,000 people as part of a series of debates called"Prove Me Wrong."
The audience was in shock at first, and then the evacuation followed.
Police and emergency services responded quickly, but Kirk soon succumbed to his injuries.