The shooting unfolded in Kingsbridge on Monday.
NYPD sources told Eyewitness News that the officer involved believed that the people in a white car had stolen his vehicle.
Surveillance video shows the off-duty officer drawing and aiming his weapon at someone, then pinning the man down behind the white car.
A single shot was fired. The bullet pierced the driver's side window of the car and hit the 30-year-old man inside. Its trajectory continued, narrowly missing a BX10 bus on its way to Norwood, and finally shattering the window of a bar across the street on West 231st Street and Albany Crescent.
The 30-year-old man in the car, who was shot in the head, remains in critical condition. Someone brought him to the hospital, possibly in that car.
The off-duty officer works in the NYPD's Intelligence Division and has had high-profile assignments at Gracie Mansion and City Hall, sources say.
The officer has been suspended without pay as the investigation continues.
No charges have been filed.
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