Suffolk County Police Seventh Squad detectives are investigating a motor vehicle crash that seriously injured a pedestrian in Shirley last night.

A man was driving a 2006 Hyundai northbound on William Floyd Parkway when the vehicle struck a pedestrian crossing the roadway from east to west at approximately 9:45 p.m.

The victim, 19, of Shirley, was transported to Stony Brook University Hospital for treatment of serious injuries. The driver, 43, of Mastic Beach, was not injured.

The vehicle was impounded for a safety check. Detectives are asking anyone with information on the crash to call the Seventh Squad at 631-852-8752.