The incident happened at the OK Petroleum, located at 2117 Middle Country Road in Centereach, at about 10:40 p.m. on Sunday, Dec. 12, according to the Suffolk County Police Department.
SCPD said a 30-year-old Centereach man left his 2003 Chevrolet unlocked and running in the parking lot and went inside the business.
When he came back to the Chevrolet, a man with a knife was sitting in the backseat of the vehicle and demanded cash from the victim, police said.
The 30-year-old man said he didn't have cash, and the suspect forced him to drive to two ATMs and withdraw money, SCPD reported.
Police said the suspect had the man drive to an alley near the gas station, and a physical altercation took place where the victim was slashed in the face.
The suspect ran away from the scene, police said.
Investigators asked anyone with information about the incident to call police at 631-854-8652 or Crime Stoppers at 1-800-220-TIPS.
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