Around 5 p.m. on Aug. 23, officers located the 42-year-old victim unconscious with a head injury in the waters off Washington Heights, the New York Police Department announced.
Investigators determined 19-year-old Miguel Cortez allegedly struck the victim in the head with a rock after the two men got into an argument near the shoreline.
The blow to the head caused the victim to tumble into the water, according to authorities.
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First responders pulled the victim out of the river and he was transported to a nearby hospital, where he died, according to police.
Cortez and the victim knew each other, but detectives have not disclosed the nature of their relationship.
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