Nearly 300 people were arrested at Columbia University and the City College of New York late Tuesday as police broke up pro-Palestinian protests and an occupation at the two campuses, officials said Wednesday. 

At a news briefing, NYPD Chief of Patrol John Chell said 282 people were arrested in connection with the protests, including 173 people at City College and 109 people at Columbia.

Police transported those arrested to NYPD headquarters in Lower Manhattan, where dozens of supporters assembled Wednesday morning.

"We often see what we call a jail support action in the aftermath of a number of arrests… and now we see the response to the protests around the release from our arrest processing center," Rebecca Weiner, deputy commissioner of intelligence and counterterrorism for the NYPD, said during an interview on "Mornings On 1.”

Weiner said the arrests were necessary given the escalation of activity over the past 36 hours.

"This had moved very clearly away from the zone of peaceful protest — away from the zone of even vile rhetoric and some of the incredibly concerning conduct that we saw last week — but into tactics involving vandalism, property damage, barricades, heavy chains, furniture, blocking, ingress and egress locations into the building, windows being smashed,” she said. “These are not the tactics of a peaceful protest. This is criminal activity.”

Weiner noted that the NYPD had been in communication with Columbia throughout the day Tuesday, and maintained the escalation had been caused by outsiders joining the college demonstration.

"From our perspective, when we see individuals who are known to us known for years involved in the professional protesting… this is a sign to us that this isn't about students expressing their views anymore, and that there really is a public safety concern," she said.

Flanked by NYPD leadership during a briefing at One Police Plaza late Wednesday morning, Mayor Eric Adams echoed both Weiner’s comments and his own remarks from Tuesday, and then went further.

“There is a movement to radicalize young people, and I’m not going to wait until it is done, and all of a sudden acknowledge the existence of it,” Adams said. “This is a global problem, that young people are being influenced by those who are professionals at radicalizing our children, and I’m not going to allow that to happen as the mayor of the city of New York.”

The mayor pointed to a letter Columbia’s president sent to the NYPD Tuesday, in which she said the school believed a protest occupation at Columbia’s Hamilton Hall had been “led by individuals who are not affiliated with the University.”

Asked how many of those arrested Tuesday night had been students versus unauthorized outsiders, both Adams and Chell said they could not yet say.

“We are processing the arrests to distinguish between who are actual students and who were not supposed to be on the ground,” Adams said. “And we pointed out yesterday these external actors with a history of escalating situations and trying to create chaos, not to peacefully protest, but create chaos.”

NYPD Commissioner Edward Caban said those arrested face preliminary charges ranging from trespassing and criminal mischief to burglary.

At an unrelated news conference Wednesday afternoon, Manhattan District Attorney Alvin Bragg said the earliest arraignments for those arrested were expected to take place starting Wednesday afternoon or evening.

Of the 282 people arrested, about 170 received summonses, with the rest being desk appearance tickets cases or cases still making their way through the system, he said. 

Bragg said part of his office's review would involve determining what the charges should be. 

“As my office does in every instance in all of our work, we will look carefully at each individual case on our docket and make decisions based on the facts and the law," he said. "That will include a thorough review of body cam footage and interviews with witnesses."

He said his office did not have a breakdown of the number of students versus outsiders involved in the protests.

On Wednesday morning, Columbia University president Minouche Shafik released a statement explaining her decision to ask the NYPD to clear protesters from campus.

"Because my first responsibility is safety, with the support of the University's Trustees, I made the decision to ask the New York City Police Department to intervene to end the occupation of Hamilton Hall and dismantle the main encampment along with a new, smaller encampment," Shafik wrote in part.

Shafik has come under fire from politicians on both the left and right in recent weeks for her handling of the demonstrations on campus.

"I know I speak for many members of our community in saying that this turn of events has filled me with deep sadness. I am sorry we reached this point," she said in the statement. "It is going to take time to heal, but I know we can do that together."

In her letter to the NYPD Tuesday, Shafik requested the NYPD remain on campus through "at least May 17" to "maintain order and ensure encampments are not reestablished."

Police officers began arresting people on Columbia’s campus Tuesday night after successfully breaching Hamilton Hall by climbing through a window, removing protesters who had barricaded themselves inside.

Police also dispersed an encampment that had been set up on the university's West Lawn for nearly two weeks.

In a news conference Wednesday evening, Columbia spokesperson Ben Chang said the university has "no further information or specifics" on those who were arrested and either expelled or suspended.

At City College, meanwhile, NY1 crews on Tuesday witnessed multiple people being detained by NYPD officers as authorities attempted to conduct crowd control efforts.

A spokesperson for the City University of New York said a significant number of demonstrators "breached" City College's campus, which is part of the CUNY system, merging with protesters who had marched from Columbia.

The spokesperson said the protesters then attempted to enter Shepard Hall before ultimately breaking into the Administration Building at City College, where they damaged office equipment and broke glass.