It happened around 7:50 a.m. Sunday, June 19 in Seaford southbound of Exit 1E on the Seaford Oyster Bay Expressway.
Officers arriving at the scene found the vehicle had hit the guard rail and then struck a tree, Nassau County Police said.
The two male occupants inside were transported to a nearby hospital for treatment.
A 23-year-old passenger sustained severe trauma and was pronounced dead by a hospital physician at approximately 8:45 a.m.
He's now been identified as Xavier Pena, age 23, of Valley Stream.
The driver is in stable condition, police said.
The investigation is ongoing.
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