UPDATE: Several Off-duty NYPD cops stood by while bikers beat dad...

 Alexian Lien's Range Rover; Inset: Lien on the ground after the attack.

Alexian Lien's Range Rover; Inset: Lien on the ground after the attack.

(NEW YORK POST) -- An off-duty, undercover NYPD cop was among the pack of bikers who chased a family up the West Side Highway — and he stood by as the dad was hauled from his car and beaten, sources told The Post.

The unidentified officer waited three days to come forward Wednesday night. He has been placed on modified duty, and turned in his gun an badge on Friday, the sources said.

He rides with the New Rochelle-based Front Line Soldiers, a club that also counts several other cops among its members, a source said.

Internal Affairs is investigating whether those cops, too, were among the bikers — and whether they also witnessed the assault that left Internet exec Alexian Lien bleeding on the pavement as his wife and toddler cowered in their black Range Rover.

“It is does not appear that he got involved at the scene,” one law enforcement source said of the undercover, who has hired a lawyer.

“He didn’t want to blow his cover,” said the source — though the cop was not investigating the group of bikers.

Cops have uncovered new photo and video evidence showing Lien was attacked by as many as five bikers, sources said.

One of those bikers was allegedly Robert Sims, 35, of Brooklyn; A source said he was taken into custody Friday afternoon.

“Apparently, he hit the guy,” the source said.

Reginald Chance, 38, of Brooklyn — depicted in video using his chrome-colored helmet to bash in Lien’s driver’s side window — remains a suspect but has not been charged. Read more via NY Post...


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