It happened on Saturday, May 23 at about 11:05 p.m. in West Islip.
Robert Ferri, 65, of Babylon, was driving a 2001 Ford sedan eastbound on Route 27A when the vehicle left the roadway and struck a tree between Admirals Drive East and Otis Lane, Suffolk County Police said.
Ferri was transported to Good Samaritan Hospital Medical Center in West Islip with serious injuries.
A 28-year-old male passenger in the vehicle was transported to the same hospital for treatment of non-life-threatening injuries.
The vehicle was impounded for a safety check.
Detectives are asking anyone with information about the crash to call the Third Squad at 631-854-8352.
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