CARSON (CBS) — Friends and family of 42-year-old murdered Homeland Security agent Myron Chisem gathered Thursday evening to mourn inside his Carson home.

Authorities say Chisem’s 14-year-old son shot his father Wednesday evening.

Earlier Thursday, a flag-draped gurney removed Chisem’s body from the home.

Juan Fernandez, reporting for CBS2 and KCAL9, said his fellow agents saluted as his body was taken away.

Fernandez spoke to Shawn Butler, a Chisem friend for the past ten years. The men met while serving in the Navy.

Butler rushed to the Chisem house the moment he heard the news about the shooting. “He served in the Persian Gulf. Became an agent about five years ago. Really loved his son. This is a tragedy. I don’t know what else to say. I’m hurt. He was my best friend.”

Investigators have not given a motive for the shooting.

Said friend Albert Johnson, “I’m shocked. Dismayed. Not really understanding what happened.” And to Johnson the tragedy makes even less sense because “everything seemed fine. We’re just searching for answers.”

Chisem’s son reportedly told authorities he was in the backyard — firing his father’s service weapon — when a bullet went through the family room and hit Chisem in the back of the head while he was watching TV.

Detectives said the 14-year-old called 911.

Chisem’s girlfriend lived with him in this home for the past nine months. She told Fernandez she was not yet ready to discuss the tragedy. The girlfriend was not home at the time of the shooting.

Chisem is also survived by two daughters.