It happened on Sunrise Highway in Patchogue at about 1:30 p.m. on Tuesday, Jan. 11, according to the Suffolk County Police Department.
David Redlo, age 58, of Bohemia, was driving a 2008 Mazda west on the highway near Exit 51 when the Mazda veered and struck a guardrail, SCPD said.
Redlo was taken to a hospital where he was pronounced dead, police said.
Police believe Redlo suffered a medical emergency before the crash.
SCPD said the Mazda was impounded for a safety check.
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