It happened around 2:30 a.m. in a parking lot outside a bar in Holbrook.
Police released this picture of the man they're looking for on Wednesday.
Police say he stabbed a man outside the Back Porch on Grundy Avenue. The victim was not seriously hurt.
Police are offering a $5,000 reward for information leading to an arrest.
Anyone with information about these incidents can contact Suffolk County Crime Stoppers to submit an anonymous tip by calling 1-800-220-TIPS, texting "SCPD" and your message to "CRIMES" (274637).
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