Police say a vehicle hit the man at just before 9:00 Friday night on the Parkway near Pine Aire in Islip.
A block away, officers found a woman who had been stabbed.
She was taken to the hospital, but it's unclear how seriously she was injured.
The man who was struck on the Parkway has not been identified.
Police say they believe the two incidents are related, but they are still investigating how.
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