Police say he was stabbed at least five times in the chest and abdomen -- possibly with a screwdriver.
It happened near Rochester Avenue and Carroll Street in the Crown Heights section just before 7 p.m. Sunday.
Officials recovered the suspected weapon near the scene and will determine if it was used to assault the victim.
The victim was apparently attacked by a group of teens who fled the park on foot.
The 16-year-old was taken to nearby Kings County Hospital.
No arrests have been made.
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