NORTHPORT, N.Y. (CBSNewYork) — A man was arrested Sunday afternoon after he allegedly stabbed a man in Northport, Long Island.

Suffolk County police said the two men, who knew each other, had been fighting outside 820 Fort Salonga Rd. around 3:15 p.m. when one stabbed the other in the abdomen.

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The man who was stabbed was taken to Northwell Health Southside Hospital for treatment of serious injuries, police said.

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The suspect, a 38-year-old man from East Northport, was charged with first-degree assault, police said.

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Police did not identify the suspect late Sunday.