Authorities charged the 14-year-old son of an Immigration and Customs Enforcement agent with murder after his father was found shot dead Wednesday night in his Carson, Calif., home, police said.

The boy allegedly fired a shot through their backyard and into the living room, using his father’s federally-issued gun. His father was shot in the head, police said. 

The boy called 911 after the shooting. Authorities have not released the name of the ICE agent who was off duty at the time, but say he worked for the agency for four years and was 40 years old. The Department of Homeland Security said he was involved in Homeland Security investigations in the Los Angeles area.

A friend for the boy, Shawn Butler, identified the victim as U.S. Immigration and Customs Enforcement agent Myron Chisem. He was about 40. 

Butler says Chisem's son moved into the home within the past year. He says he never saw any trouble between the two.

The shooting occurred between 9 p.m. and 9:15 p.m. The motive of the shooting is unclear. Homicide detectives from the Los Angeles County Sheriff’s Department are on the scene.

In a separate shooting, three homeland security officers were shot in Petaluma, Calif., and taken to a nearby hospital with serious injuries. The officers were apparently shot while executing high-risk federal warrants related to an ongoing criminal investigation.  

Fox News' Edmund DeMarche and the Associated Press contributed to this report.