New York (CNN) -- New York police have arrested one of their own on riot and criminal mischief charges in connection with the September 29 attack on an SUV driver in New York City, a law enforcement official said Tuesday.
Wojciech Braszczok, a 32-year-old detective in the New York Police Department who was off duty at the time, is allegedly shown on a video smashing the rear window of the Range Rover as it drove amid a sea of motorcyclists on the city's West Side Highway, according to the official. That video is now in investigators' hands.
It is not clear if the detective participated in the subsequent beating of the vehicle's driver, Alexian Lien.
Both charges Braszczok faces are felonies, according to the law enforcement official.
Braszczok was one of at least two off-duty undercover officers who were riding with fellow bikers that day, a law enforcement official told CNN. The other officer, who is under investigation, has been talking with authorities about the incident, a law enforcement source said.
Braszczok was riding with his motorcycle club when the incident occurred and saw much of the confrontation, a law enforcement source told CNN last week. The undercover officer allegedly didn't inform supervisors about the incident until three days later, telling internal affairs investigators that he waited because he reportedly was afraid his cover would be blown. The second off-duty officer now being questioned also waited a few days to report the incident, the law enforcement source said.
Braszczok is expected to be arraigned Wednesday.
Once the prosecutor formally brings charges against him, six people in total -- all of them motorcyclists -- will have been charged in the case.
"In the last few days, serious charges have been brought against several defendants in last Sunday's attack," Erin Duggan, a spokeswoman for the Manhattan district attorney's office, said Wednesday. "As we said from the beginning of the investigation, the NYPD and the District Attorney's Office are methodically scrutinizing the evidence to build the strongest possible cases in our continuing effort to hold accountable those responsible."
The five other motorcyclists are:
• Clint Caldwell, a 32-year-old biker from Brooklyn, faces charges of gang assault, assault and criminal mischief. Police have video allegedly showing him at the scene of the attack, according to New York police Lt. John Grimpel. He too will be arraigned Wednesday.
• Craig Wright, 29, was arraigned Tuesday on gang assault and other charges and then ordered held on $150,000 bond. Wright is accused of stomping Lien at least twice after police say he and other motorcyclists forced the man's Range Rover to a stop, used their helmets to break out the window and dragged him out of the car, in which his wife and 2-year-old daughter were passengers.
A witness who tried to help the driver told CNN on Tuesday that bikers also tried to drag Lien's wife from the vehicle.
According to court documents, police say Wright, 29, identified himself in a picture showing him standing near the stopped SUV. Another photograph shows him stomping Lien as the man lies on the ground, according to the documents.
Wright is charged with first-degree gang assault, first-degree assault and first-degree unlawful imprisonment. He was arrested at his home in Brooklyn.
In addition to the bond, New York Trial Court Judge Tamiko Amaker set Wright's next court date for Friday.
In March, Wright pleaded guilty to driving with a suspended license, a spokesman for the Brooklyn district attorney's office said. It is unclear whether he was driving with a suspended license at the time of the SUV incident.
He was also convicted in Virginia in 2005 for reckless driving.
• Reginald Chance, 37, who was captured on video smashing his helmet into the SUV's window, has been charged with first-degree assault and gang assault. He was ordered held on $75,000 bond Sunday.
Assistant District Attorney Samantha Turino said Chance's license had been suspended and he should not have been driving. She said his arrest record includes a marijuana charge in 2013 and attempted criminal possession of a weapon in 2006.
"The law does permit someone who is a victim of an accident to at least attempt to get the identification of the motorist," said Chance's attorney, Gregory Watts. "My client obviously overreacted in that manner, but he is not this thug assaulting someone who's harmless, contrary to the public opinion that's being put out there."
He said Chance was knocked off his motorcycle by Lien's SUV after bikers had surrounded the vehicle earlier.
• Christopher Cruz, 28, who police say is the biker who slowed in front of Lien, was charged with reckless driving and other misdemeanors. He was released on bond.
His lawyer, H. Benjamin Perez, said, "He never tried to assault him in any way. And he does not know any of the other motorcyclists who were involved in this beating."
• Robert Sims, 35, is accused of stomping on Lien. He surrendered Friday on charges of attempted assault and gang assault.
The case became national news after video of the incident surfaced.
The video was captured, attorney Andrew Vecere said, when his client, motorcyclist Kevin Bresloff, turned on his helmet camera after he saw a water bottle thrown from the SUV's sunroof toward the bikers. It shows dozens of bikers swarming on Manhattan's West Side Highway. One motorcycle quickly slowed down in front of Lien, who bumped its rear tire, slightly injuring Cruz.
Lien pulled to a stop, and angry bikers surrounded his vehicle, hitting it and spiking its tires, police said.
Lien's vehicle plowed into three more bikers, including Edwin Mieses, whose wife says he is paralyzed.
Edwin Mieses is still in great pain, Dayana Mieses said Tuesday, but he's out of the intensive care unit. A doctor told them "there's a 99% chance my husband will never walk again," she said.
The video shows the Range Rover stopping again -- long enough for a biker to open the door -- and Lien then driving away until traffic forced him to the final stop.
Police say the subsequent beating included kicks to Lien's head and body as he lay on the highway. Lien suffered two black eyes and cuts on his face and side, requiring stitches, a police detective's criminal complaint said.
His wife and daughter were unharmed.
Defenders of the bikers, including relatives of Mieses, the critically injured biker, have criticized Lien for driving through the crowd of motorcycles.
Vecere, Bresloff's attorney, says his client hasn't been charged with a crime, and he doesn't expect him to be. He said police issued a warrant for the video, but Bresloff was going to turn it over anyway. He's cooperating with police, Vecere said.
"He was shocked" by what happened, the attorney said, adding that the case is "not black and white."
CNN's Laura Dolan, Rob Frehse, Yon Pomrenze, Eden Pontz and Greg Botelho contributed to this report.