Arizona police: 4-year-old boy fatally shoots his father

(CNN) -- A man was fatally wounded when his 4-year-old son fired a gun he found while they were visiting a residence in Prescott, Arizona, officials said.

Justin Stanfield Thomas, 35, and his son made an unannounced trip Friday to the home of an unidentified former roommate, police said. Thomas had previously lived in the residence, according to investigators.

"This appears to be an accident. There was no conflict in the stories of those in the house," said police Sgt. Brandon Bonney. "The resident didn't know his former roommate was stopping by to visit."

Moments after arriving at the home, the boy picked up the small-caliber handgun and asked his father and other adults in the room what it was he was holding, said Bonney.

Seconds later he pulled the trigger.

Officers and emergency crews arrived and found Thomas, of Phoenix, with a single gunshot wound to the chest. He was transported to a local hospital, where he was pronounced dead.

Acknowledging it appears to have been a tragic accident, Bonney cautioned gun owners

"We want to remind people without making a villain of this person, that if a child is visiting your home, the first thing to do would be put the firearm away."

No charges were anticipated because the incident was an accident, Bonney told CNN.