Oct. 6, 2013 -- Two off-duty New York police officers were riding with the biker group whose members allegedly assaulted an SUV driver in New York City, and the NYPD is investigating why the cops apparently did not intervene, authorities said.
Among those off duty officers was an undercover narcotics cop who came forward to his superiors days after the incident, according to officials. He did not get involved in the beating out of fear that his cover would be blown, sources said.
The cop's identity has not been released by the NYPD. The officer's involvement was also the subject of an Internal Affairs investigation, sources said.
Another other off-duty officer riding with the group was also believed to have been nearby when the incident occurred, sources said.
Investigators are also looking into reports that there were three other off-duty cops who may have been near the sport bike ride that ended with the alleged attack on Range Rover driver Alexian Lien, but were not close enough to see the incident, officials told ABC News.
Lien was driving his SUV on the West Side Highway in Manhattan with his wife and 2-year-old as part of a wedding anniversary celebration around 2 p.m. Sunday, Sept. 29, when their SUV was surrounded by the motorcyclists, who were doing an annual ride through the city, police and Lien's wife said.
The bikers tried to slow traffic and one biker cut Lien off, slowing down and leading Lien to bump into the biker, police said. The group of motorcyclists then slowed down further and surrounded the SUV, and in response Lien accelerated away from the group.
Lien's wife, Rosalyn Ng, said her husband feared for their lives when he decided to take off to get away from the group. As he sped off, Lien hit some of the motorcyclists, critically injuring one, authorities said.
Other motorcyclists chased Lien's SUV and then bashed in his windows, pulled him out of the car, and beat him, police said.
Two men seen on video committing the most violent actions at the scene are in custody.
Robert Sims, 35, who allegedly grabbed the SUV's door about five minutes into the video, turned himself in to police Friday in Brooklyn, NYPD officials said.
He faces charges of gang assault, assault and criminal possession of a weapon, police said this morning.
Sims was arrested in 1998 for possession of a loaded firearm and a samurai sword, and he served eight months in jail, police said.
Reginald Chance, 38, of Brooklyn, also surrendered to police late Friday. He allegedly was the man seen on video using his helmet to smash the driver's side window of the Range Rover before the video cut off and the alleged assault took place.
Chance's possible role in the alleged assault beyond the window smashing was not immediately clear.
He was arraigned today in Manhattan Criminal Court on charges of gang assault, assault in the first degree, criminal possession of a weapon, menacing, and criminal mischief.
His bail was set at $100,000 bond or $75,000 cash, and he was due to return to court Oct. 11.
Chance and his attorney conceded the criminal mischief charge, admitting that Chance smashed in the window of the SUV, but said they will fight all the other charges.
Chance's attorney, Gregory Watts, said Chance was not a participant in any gang assault and that his client was a victim. He asked for a separate grand jury to investigate whether Lien committed a crime by driving into other cyclists, including his client.
Meanwhile, Sergio Consuegra, who is seen in NYPD fliers with his arms stretched out protecting Lien from the bikers, was honored in Washington Heights today for his bravery.
Consuegra told ABC station WABC-TV in New York that he intervened in the beating when he saw a biker grabbing Ng through the car window, telling her, "You're going to get it too."
Newly released photos show the SUV's passenger side window where Ng was sitting was smashed in, as well as the driver's side window.
"At that moment, I said I have to do something," Consuegra said. "There's a family in danger here and they're going to get killed. Nobody intervened in this situation and nobody's stepping in."
Consuegra said the biker left Ng alone after the crowd began screaming for help. Then, he said he saw a badly bloodied Lien on the ground, getting bashed in the head with a helmet.
"I went up there, right away to them, and I stood in the middle," he said. "I went, 'No. No, that's it. Let it go guys. You did what you did.'
"Then somehow, one of them moved, started moving and I said, 'Yeah, this is enough now,'" he said.
ABC News' Alexis Shaw contributed to this report.