It happened just before dawn around 6 a.m. along a busy stretch of 9W near Fairmount Avenue in Haverstraw.
The victim, 82-year-old Juan Alberto Germonsen, who lived in the nearby Green Hills Home for Adults, is believed to have been crossing the street when he was struck.
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The driver kept on going.
Germonsen was found lying in the roadway and was rushed to the hospital, where he was pronounced dead.
Investigators were at the scene all morning, collecting evidence and gathering a description of the vehicle.
"Our detectives are trying to look at local surveillance videos from homes and businesses," Haverstraw police Lieutenant John Gould said. "And we're in the process of gathering that information right now."
Officials say residents of the home sometimes walk along to roadway to get to the nearby village.
The suspect vehicle is described as a silver or white Ford Explorer with dark rims and a moonroof, and police said it should be missing the passenger side mirror and have damage to the front passenger side bumper.
The investigation is active and ongoing, and anyone with information is urged to contact police.
Anyone who may have any information or may have witnessed the incident is asked to contact the Town of Haverstraw Police Department at (845) 354-1500.
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