New York City’s mayor, Zohran Mamdani, and other local officials on Monday condemned Immigration and Customs Enforcement (ICE) after federal officers dragged a man out of a hospital building where he had been taken following an arrest, prompting a crowd of protesters to gather outside, where they clashed with police.

The incident over the weekend has also drawn scrutiny from critics questioning the New York police department’s response at the scene, in relation to New York City’s sanctuary laws, which bar local police from assisting federal immigration authorities in civil immigration enforcement.

The incident unfolded on Saturday night outside the Wyckoff Heights medical center in the Bushwick neighborhood of Brooklyn, where dozens began gathering after reports that ICE officers had brought in a man they had detained.

The Department of Homeland Security (DHS), the parent agency of ICE, said in a statement on Sunday that agents had been conducting “a targeted enforcement operation” in Brooklyn that “resulted in the arrest of Chidozie Wilson Okeke”, a Nigerian citizen. The agency said he had overstayed a tourist visa and also had been previously arrested for assault and drug possession, though it did not provide further details.

The DHS said that during the arrest Okeke had refused to comply with officers’ orders, and that a physical tussle occurred, during which agents used force to make the arrest. The DHS added that Okeke then requested medical attention, prompting agents to bring him to the hospital for evaluation.

The DHS said that a “significant” crowd then formed outside the hospital.

The NYPD has said that officers responded to reports of “multiple disorderly groups” near the hospital.

“Upon arrival, officers observed numerous individuals acting in a disorderly manner, obstructing vehicular traffic, and blocking emergency entrances and exits at Wyckoff Heights medical center,” the police said.

In the early hours of Sunday, video clips circulating online show ICE dragging the detained man out of the hospital in handcuffs and putting him into a waiting car, while protesters clashed with police.

The NYPD said it was not involved in the federal immigration operation and only responded to the scene after receiving 911 calls about the crowd, saying they received initial reports that there were about 200 protesters.

Police issued verbal warnings for individuals to disperse and return to the sidewalks and eight people were arrested and charged with resisting arrest, obstructing governmental administration and reckless endangerment, the NYPD said.

Sandy Nurse, a New York city council member who was present, wrote on social media that she went to “observe our community responding to news that ICE was there”, adding: “New Yorkers showed up immediately.”

On Monday, she said it was unclear whether the way NYPD acted, particularly in putting themselves between protesters and the ambulance bay where ICE brought the man out, violated the city’s sanctuary laws, but it was vital to know so that local elected officials can communicate the best way for their constituents to be safe.

“If it’s not [a violation], then there should be a clear ability to say in moments like that, that the NYPD will facilitate a secure exit of ICE with a detainee. If it does [violate], then there needs to be accountability,” she said, in a phone interview. “It’s not my job, it’s the [Mamdani] administration’s job and it’s the police commissioner’s job to provide clarity to New Yorkers on what can be expected – and … we can make a determination: does the sanctuary city law need to be even more detailed?”

The NYPD said in a statement that it does not conduct or participate in civil immigration enforcement, and had “no prior awareness or coordination” regarding the ICE operation that took place on Saturday night.

Mamdani’s office did not immediately respond to a request for further comment. At a news conference on Monday morning, the mayor said: “I want to be very clear, there was no prior coordination nor planning between the NYPD and ICE ahead of this incident, NYPD officers were not dispatched to the hospital to participate or facilitate an ICE operation, rather they were responding to 911 calls regarding a protest outside of the hospital.”

He added: “Our laws leave nothing, no room for interpretation, about the fact that our NYPD will not participate in civil immigration enforcement, and I’ve also been very clear about my views on ICE raids as a whole. I think that they are cruel, I think that they are inhumane and I think that they do not serve any interests of public safety.”

Mamdani said that he had seen some videos from the incident, including one that he said showed an NYPD officer “grabbing a New Yorker and throwing them on to the floor”.

“That is incredibly disturbing and that is being actively investigated right now,” Mamdani said.

An immigration activist who attended the protest and did not want to be named because she fears repercussions from law enforcement said that she hopes that Mamdani will rise to the occasion. “We need the mayor to stand on the side of our communities and our neighbors, and what that looks like is telling the NYPD to back off,” she said.

In a social media post on Saturday, the Brooklyn borough president, Antonio Reynoso, said: “ICE’s presence in Bushwick is deeply alarming …

“To our neighbors who quickly mobilized last night, thank you for making it loud and clear that ICE is not welcome in Brooklyn.”

The New York state senator Julia Salazar, whose district includes Bushwick, also said on social media that ICE appears “to have significantly increased its presence in Bushwick recently”.

“It’s also concerning that this many NYPD officers were deployed for what was clearly a justified gathering by local residents,” she added.

Murad Awawdeh, president of the New York Immigration Coalition, said the events reinforce the need for stronger sanctuary protections that clearly define what collusion looks like.

“This is where it falls in a gray area,” Awawdeh said. “You have a local law that says NYPD cannot collude on civil immigration enforcement and the action that ICE did was civil immigration enforcement. Then you have the NYPD being called … to support in clearing the street. How do you define non-collusion in a moment like that?”

Awawdeh also called for an investigation into the NYPD’s actions and for police to drop charges against the arrested protesters.

Donald Trump retook the White House with an agenda of mass deportation, and his Republican administration favors targeting sanctuary cities, especially larger, Democratic-run cities, although New York has so far avoided the large-scale ICE and border patrol sweeps that brought violence and chaos to parts of Los Angeles, Chicago and Minneapolis.