Joseph DeMarie, 45, was operating a Yamaha ATV without a helmet on Glen Summer Road in Holbrook when he apparently lost control of the vehicle and fell to the ground at approximately 11:45 a.m. Sunday, Nov. 17, Suffolk County Police said.
DeMarie, of Holbrook, was transported via Holbrook Fire Department ambulance to Stony Brook University Hospital with serious injuries.
The ATV was impounded for a safety check.
Anyone with information is asked to call the Fifth Squad 631-854-8552.
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