The incident happened around 9 p.m. Thursday, July 23 in Brentwood.
Dinorah Pantaleon, 38, was driving a 2011 Honda Pilot southbound on Fifth Avenue, near the intersection of Third Avenue, when her vehicle struck the man walking eastbound on Fifth Avenue, Suffolk County Police said.
The pedestrian, Juan Martinez-Umana, 45, who is undomiciled, was transported to Southside Hospital in Bay Shore for treatment of serious injuries.
Pantaleon, of Bay Shore, was not injured.
The vehicle was impounded for a safety check.
Anyone with information on the crash is asked to call the Third Squad at 631-854-8352.
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