An NYPD detective was captured on video participating in last week's biker mob attack on a black SUV, anonymous police sources told NBC News.
According to NBC's sources, who spoke only on the condition of anonymity, a new video depicts a detective smashing open the rear window of the Range Rover. When the driver is drug out of his vehicle, the officer reportedly drove off the scene.
Investigators learned of the video, which is not the same one widely circulated on the Internet, Monday, according to NBC.
A shocking image shows Lien, 33, being pulled out of his vehicle and beaten in front of his wife and child. (Image source: New York Daily News/Instagram user REDYREDBX)
Initial reports said the undercover officer stood by as the SUV was attacked because he didn't want to "blow his cover." One law enforcement officer even said it "does not appear that he got involved at the scene."
On Monday, a fourth suspect was arrested for allegedly taking part in the biker-mob chase and assault.
Craig Writer, 29, has been charged with gang assault, assault and unlawful imprisonment, according to WABC.
On Sunday 37-year-old Reginald Chance, another biker charged with assault in connection to the attack, flipped off reporters in court.
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