A 35-year-old Army veteran died after being accidentally shot by his 4-year-old son while visiting a friend, KNXV-TV reported on Friday.

Police told the station that Justin Stanfield Thomas, who served as a member of the Green Berets during the Iraq war, and the boy were visiting a former roommate in Prescott Valley, Arizona. The friend, who was allegedly not expecting the visit, did not have his gun locked away at the time.

"Within minutes the little boy found the gun, said 'Daddy, what's this?'," a neighbor, Jeremy Hartt, said to KNXV. "Then, it went off."

Authorities found Thomas after responding to reports of shots fired at the residence. He was pronounced dead at a local hospital.

Hartt said to the station that Thomas' friend, who was not identified, was a fellow former service member who kept a firearm for protection.

The boy was released into the custody of his mother. Hartt told KNXV that he did not understand what happened after the gun went off.

Watch the station's report on the shooting, which police determined to be accidental, below.