Video of NYPD officer 'punching 16-year-old boy' as he is arrested emerges

Incident is being investigated by the NYPD internal affairs bureau

A man is seen running in and punching the teenager (YouTube )

A shocking video has emerged of a teenage boy being repeatedly punched as he is arrested by a man believed to be a plain-clothes New York police officer.

Footage captured by actress Sarah Doneghy shows the unidentified boy being handcuffed by three uniformed New York Police Department (NYPD) officers on the bonnet of a car. Another officer can be seen standing at the side.

As the boy appears to be struggling, another man runs in and begins to punch him repeatedly.

A woman can be heard shouting in the background: “Hey! Hey! Hey! Stop it! Get off him!”

Another witness can be heard saying: “Why did you just do that? […] I’m a lawyer, I can’t believe you just did that. After everything that’s happening.”

Her comments appear to refer to Eric Garner, a 43-year-old black man who died when a white police officer in New York restrained him in a chokehold.

The father-of-six repeatedly gasped "I can't breathe!" in an arrest that was captured on video.

Ms Doneghy, who uploaded the video to YouTube, had believed the boy was only 12-years-old.

The NYPD later confirmed he was actually 16.

When contacted by The Independent, a NYPD spokesperson said the incident is under review and allegations are being reviewed by its internal affairs bureau.

It would not comment on the incident any further.