It happened at about 9:45 p.m. Sunday, July 28 in Bohemia.
A 24-year-old Sayville man was driving a 2017 Nissan Altima southbound on Oakdale-Bohemia Road when the vehicle struck the pedestrian on the Sunrise Highway overpass, Suffolk County Police said.
The man initially left the scene in the Nissan, then returned approximately 20 minutes later, police said.
The victim, Christopher Gallagher, 42, of Bohemia, was pronounced dead at the scene by a physician assistant from the office of the Suffolk County Medical Examiner.
The Nissan was impounded for a safety check.
The investigation is continuing and detectives are asking anyone with information on this crash to call the Major Case Unit at 631-852-6555. All calls will be kept confidential.
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