The crash occurred approximately 1,000 feet west of Gazzola Drive, at approximately 4:30 a.m. Sunday, April 28, Suffolk Police said.
Officers were dispatched after a passing motorist called 911 to report a body in the roadway, police said.
Detectives determined the bicyclist, Alexis Velasquez, was traveling eastbound when he was stuck by an eastbound vehicle that fled the scene.
Velasquez was pronounced dead at the scene by a physician assistant from the Office of the Suffolk County Medical Examiner.
Detectives believe the vehicle that struck Velasquez is a silver or gray Nissan SUV with front-end damage.
Anyone with information on this crash is asked to call Major Case Unit detectives at 631-852-6553 or anonymously to Crime Stoppers at 1-800-220-TIPS. All calls will be kept confidential.
This is a developing story. Check back to Daily Voice for updates.
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