The incident happened in Central Islip, outside a business on Brightside Avenue near Islip Avenue, shortly after 4 p.m. Thursday, Oct. 31.
Suffolk County Police said a man was sitting in the driver’s seat while parked in a lot outside the Hands Across Long Island mental health services building when a man opened his door and stabbed him with a knife.
The suspect, who was wearing a Halloween mask, then fled the scene.
The victim was taken to a hospital and treated for non-life-threatening injuries.
No suspects had been identified or arrested as of Friday, Nov. 1.
Anyone with information is asked to contact the Suffolk County Police Department at 631-854-8352 or Crime Stoppers at 1-800-220-TIPS.
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