The incident happened at Tanner Park Marina in Copiague at about 4:45 p.m. on Saturday, Oct. 29, the Suffolk County Police Department said.
SCPD said a Town of Babylon park ranger was responding to a complaint about a suspicious person when the man lunged at him.
The park ranger shot the man once in the chest, police said.
The man was hospitalized for treatment of serious injuries, and the park ranger was taken to a hospital for evaluation, authorities said.
Police did not release the identities of the park ranger or the man.
An investigation into the shooting is ongoing.
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