A 4-year-old boy drowned in a swimming pool at a backyard barbecue Saturday night in Shirley.

Police say the incident happened at around 7 p.m. at 44 Alcolade Drive East. The boy was with his mother at the party, which was at the house of her friend.

The host of the barbecue discovered Justin McConville at the bottom of the 4-foot, above-ground pool.

According to police, the boy was pulled from the pool and CPR was performed by his family until an ambulance arrived. McConville was taken to Brookhaven Memorial Hospital Medical Center, where he was pronounced dead.

Police say an investigation into the drowning is ongoing.

This incident marks the sixth drowning in Suffolk County since around this time last year.