In a video shot on Sunday, Jhamal Gonsalves makes a right turn on his moped as a Providence, R.I., police cruiser pursues him. Gonsalves had been riding with a crowd of dirt bikers that police were trying to get off the streets. As Gonsalves momentarily shifts off frame, the police car’s tires screech and a loud crash echoes.

When the video swings back, it finds the 24-year-old man lying motionless after flying through the air and smashing onto the pavement. Gonsalves, who suffered swelling and bleeding to his brain and had to be intubated at a hospital, is now in a coma, his family said this week.

The incident, which is now being investigated by the Providence Police Department and the Rhode Island Attorney General’s Office, has rocked the state. On Tuesday night, hundreds of protesters rode dirt bikes and marched through Providence, later clashing with police, who arrested 19 people and said one officer was injured.

“He didn’t commit a big crime. He was just out riding with a bunch of friends,” Gonsalves’s mother, Tia Tribble, said to WPRI. “I just want my son back.”

Critics have called for the arrest of Kyle Endres, the Providence police officer behind the wheel during the crash. Endres, a six-year veteran of the force, was placed on administrative desk duty until the investigation is completed, the Providence Journal reported.

“We want the officer to be held accountable,” Bernard Tribble, Gonsalves’s stepfather, said to WBZ. “He hit a 24-year-old on a scooter, [that’s] excessive force.”

But police contend that it’s still unclear whether Endres actually hit Gonsalves. That question is expected to serve as the major focus of the investigation over the next two weeks, Providence Police Chief Hugh T. Clements Jr. said in a news conference Monday. Providence Mayor Jorge Elorza (D) told reporters that the investigation would be “thorough and complete.”

Investigators will consider whether Endres hit the moped or if the officer struck a stop sign that then slammed into Gonsalves. Providence Public Safety Commissioner Steven Pare indicated to WJAR that the investigation would also examine whether Gonsalves and Endres both quickly turned to avoid a separate police cruiser that was pulling out.

One witness who recorded a viral video of the crash told WLNE that the police cruiser hit both the moped and a stop sign.

“You could hear it clearly,” Mark Gonsalves, the rider’s father, said to WJAR of the video capturing the crash. “You could hear the impact.”

In the hours leading up to the crash Sunday, police say they were following hundreds of ATV and motorbike riders driving through the city, many of whom were riding bikes that were not street legal. Providence’s “no chase” guidelines against police pursuing dirt bikes and illegal ATVs riding through the city have come under fire in recent months from lawmakers after accidents over the summer sent people to the hospital, GoLocalProv reported. Although Jhamal Gonsalves was wearing a helmet and his scooter was street legal, Clements noted that his moped was unregistered and did not have a license plate. (Gonsalves’s mother disputed that her son’s moped was unregistered.)

Moments after the 24-year-old was thrown from his moped, police surrounded the unconscious Gonsalves and called for medical assistance. The first officer to reach the fallen rider appeared to drag him by his right arm, according to the video.

“Yo, they just f------ crashed him,” said a man recording the incident.

The man taping the aftermath confronted a police officer at the scene, saying that authorities “shouldn’t have hit him with the car like that.”

“Nobody hit him with a car,” the officer replied.

Gonsalves, who works at a shipyard in Newport, R.I., has had a love of riding anything with two wheels since he got his first bike at the age of 6, his father recalled. Gonsalves’s cousin, Paul Gonsalves, called him “the best rider I have ever met,” and wondered if police’s immediate reaction to the crash would have been different if he were White. The 20-year-old cousin raised doubts to the Journal that someone so skilled could have crashed the moped himself.

“I know that would never happen,” he said. He added, “He was 100 percent a victim.”

But others, like Providence Police Officers Union President Michael Imondi, blamed misinformation and social media for making the incident out to be an act of police brutality during a time of national unrest.

“There’s no damage on the bike,” Imondi said to WJAR. “Clearly, if he hit him, there would be damage on the bike.”

On Tuesday, a largely peaceful demonstration in the streets, including dozens riding their dirt bikes in support of Jhamal Gonsalves, escalated later into the night. The police chief described a contentious scene in which protesters shot off fireworks in the streets and tossed bricks, rocks and bottles at officers, hitting several.

Tuesday was already devastating for Kendra Thibault, who is engaged to Gonsalves. It was her birthday and her fiance, who she had been saving up money with to buy a house, remained in critical condition at Rhode Island Hospital. After nine years together, she said it felt awful not to have Gonsalves with her.

“All Id like for my birthday is some positive progress for my other half,” she wrote on Facebook. “This all just seems like a bad nightmare I can’t wake up from.”