The incident happened just after 8 p.m. Thursday, March 25 in Mastic.
Jonathan Soltan, age 24, of Manorville, was driving a 2009 Mazda 6 northbound on Titmus Drive when his car struck Jose Manuel Diaz Orellana, age 31, of Mastic, Suffolk County Police said.
Diaz, who was crossing the street when he was hit, was transported to Stony Brook University Hospital in critical condition, according to police.
On Tuesday morning, March 30, police announced he died from his injuries.
Soltan was not injured, police said.
The vehicle was impounded for a safety check.
Anyone with information on the crash is asked to contact the Seventh Squad at 631-852-8752.
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