The incident took place in Central Islip around 12:30 p.m., Saturday, Oct. 1.
According to Suffolk County detectives, Carlos Guillen was driving an Acura eastbound on Francisco Avenue when he struck a parked trailer and fence at the intersection of Lurcott Lane.
Guillen was transported to South Shore University Hospital in Bay Shore where physicians discovered a bullet wound, police said.
Guillen, age 19, of Bay Shore, was pronounced dead a short time later.
Detectives are looking to determine the location of the shooting.
Anyone with information is asked to call the Homicide Squad at 631-852-6394 or Crime Stoppers at 1-800-220-TIPS.
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