William Thomas, 60, died around 4:50 p.m., Tuesday, June 11, after crashing while driving on the Long Island Expressway, said the Suffolk County Police.
Thomas was driving a 2014 Jeep Patriot westbound on the LIE, just east of exit 70, when it veered off the road and overturned, police said.
Detectives believe Thomas suffered a medical event prior to the crash.
A passenger in the Jeep, Catherine Lucero, 55, of Riverhead, was uninjured.
Thomas was pronounced dead at the scene by a physician assistant from the Office of the Suffolk County Medical Examiner.
The vehicle was impounded for a safety check. An investigation into the crash is ongoing.
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