It happened on Monday, Oct. 28 just after 9:15 p.m. in East Islip.
John Dempsey, 60, of West Islip, was crossing Carleton Avenue eastbound, just south of Jefferson Street, when he was struck by a southbound 2002 Toyota Corolla, according to Suffolk County Police.
Dempsey was transported to Southside Hospital in Bay Shore for treatment of serious injuries.
The driver of the Toyota, Joseph Ladonna, 51, of East Islip, was not injured.
The vehicle was impounded for a safety check. Detectives are asking anyone with information on this crash to call the Third Squad at 631-854-8352.
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