Five off-duty New York City Police Department officers were reportedly part of a large group of motorcyclists that assaulted a driver over the weekend.
According to WABC-TV, at least two of the officers, both of whom are detectives, were direct witnesses to the attack on the driver, Alexian Lien.
It is unclear what the roles the other three officers played.
An undercover detective has informed Internal Affairs that he was present at the time of the confrontation.
The undercover narcotics detective, himself a motorcycle rider, was off duty. Official sources say he did not get involved because he did not want to blow his cover. Internal Affairs is now investigating. The undercover detective is being advised by an attorney.
NYPD is also investigating reports that several other members of the group were off-duty New York City correctional officers.
A video of the confrontation between the motorcyclists and Lien went viral soon after a video of the assault was posted to YouTube.