Two Utah police officers were killed and a third was injured along with his service dog when they were fired upon by a suspect inside a home while responding to a domestic disturbance Sunday night. The shooting unfolded in Tremonton, about 70 miles north of Salt Lake City, Brigham City Police Chief Chad Reyes said at a news conference Monday.

The officers were responding to a domestic disturbance on Sunday when a man came outside and opened fire, the police said.

The ATF is helping investigate the case due to discovery of improvised explosive devices at the suspect’s home.