A deranged man socked a little boy in the mouth inside a West Side park on Wednesday, police said.
The 7-year-old victim was with his father on 12th Ave. near W. 57th St. when the disturbed man punched him and knocked out a tooth at 10:30 a.m., cops said.
A witness flagged down a passing state trooper and pointed out the violent vagrant, who was still in the area.
The man resisted when the trooper tried to arrest him and was taken to Mount Sinai Hospital for a psychiatric evaluation.
State Police were still trying to figure out his identity. Charges were pending.
The child was taken to Mount Sinai/St. Luke’s Hospital.