Utah fire officials say this weekend's "Range Fire" in Provo and American Fork canyons was started by police target shooting.
An Orem Police officer using the department's gun range allegedly started the fire and is cooperating with authorities.
The Range Fire has encompassed 3,450 acres and is currently only 10-percent contained.
Homeowners in the area were evacuated Saturday, but were allowed to return to their homes Sunday.
Traffic continues to be affected by the fire as SR-92 remains closed in both directions between U.S. 189 and Cascade Springs Dr. The eastbound lanes of U.S. 189 have reopened, but the westbound lanes remain closed to allow fire crews to work safely along the roadway.
Authorities say an investigation into the fire is ongoing.
