It happened around 4:30 p.m. on Friday, Feb. 16 in Manorville.
A 26-year-old was driving a 1997 Jeep Cherokee northbound on Barnes Road near Moriches-Middle Island Road when he lost control of the vehicle, which left the roadway.
The vehicle then struck a fire hydrant and overturned.
The victim, a resident of Mastic Beach, was transported to Stony Brook University Hospital with serious injuries.
Anyone with information on the crash is asked to call the Suffolk County PD Seventh Squad at 631-852-8752.
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