The 10-year-old son of a New York City policeman shot himself in the head while playing with a gun and was hospitalized and on life-support Monday, authorities said.

Tyler Dunne's mother and 8-year-old sister were home with him when he got hold of the .38-caliber gun, hidden in a basement closet, around 6:15 p.m. Sunday, according to Lt. Dennis Farrell, commander of the Nassau County Homicide Squad. Nassau County is east of New York City on Long Island.

The boy had used a stepladder to reach a top shelf in the closet, apparently looking for a ball his mother had taken away from him earlier in the day, when he happened upon the loaded gun, Farrell said. He and his sister were playing with the gun when it accidentally fired.

Their mother heard the shot, ran to the basement, discovered her wounded son and called the emergency dispatcher. Tyler was listed in critical condition, according to Shelley Lotenberg, spokeswoman for the Nassau University Medical Center in East Meadow.

The boy's father, Joseph Dunne, 38, a 14-year veteran of the New York Police Department, was at work when the accident occurred.

Dunne often carried the privately owned and licensed gun when he traveled to and from work, but he did not usually bring it into the house, according to Farrell.

Neighbors, who said the boy used to play ball with his dad outside their home, were saddened by the shooting.

"It's terrible," Ernie Anspake said. "Horrendous. It's unbelievable."