The St. Clair County Sheriff's Department is investigating a one-car accident that claimed the life of a passenger.

David L.K. Douthitt, 24 of Belleville, was trapped Sunday evening inside a vehicle driven by Steven M. Shamrock, 22 of Belleville. The accident took place at 7:20 p.m., according to Sheriff's Department Chief Investigator Scott Weymouth.

Shamrock told deputies he was driving his 1999 Oldsmobile in the 2300 block of Imbs Station Road when he hydroplaned on wet roads and went into the ditch and overturned.

Douthitt was unresponsive as a rescue crew worked to free him from the vehicle. He was declared dead by St. Clair County Deputy Coroner Dean Darnall at 8:40 p.m.

Shamrock was transported by ambulance to St. Anthony's Hospital in St. Louis for treatment of his injuries.