The deaths of three college students near the University of Wyoming campus early Sunday were the result of a double murder-suicide, the Laramie Police Department has concluded.

The police department announced Wednesday that it believes Justin Geiger, 20, of South Beloit, Ill., killed Amber N. Carlson, 19, of Denver, with a high-powered rifle. They say Geiger also killed Adam Towler, 20, of Laramie, with a knife before killing himself with the rifle.

Geiger also stabbed another man, Anthony Klochak, 19, of Chardon, Ohio, police said. Klochak survived and fled the residence and has been cooperating with the police investigation.

Geiger, Carlson and Klochak were UW students; Towler had attended Emory University and planned to transfer to Georgetown University in the fall.

Commander Dale A. Stalder of the Laramie Police Department said the investigation into the case will continue. He said investigators didn't know the motive and weren't clear about how long the attacks took place. He said police were called to the Laramie house, where Klochak and Geiger were roommates, about 2:10 a.m.

"Absolutely the investigation is continuing," Stalder said. "We felt that it was important due to the nature of this incident, and its impact on the community, to at least try to come to some preliminary conclusions, and try to let people know as much as we can tell about this incident."