NYC Mayor Zohran Mamdani is threatening legal action against ICE over reports that agents have used city-owned lots for immigration operations, saying New York will not be complicit in actions that threaten residents’ safety.

In a letter to Department of Homeland Security Secretary Markwayne Mullin, Mamdani sought explicit guidance barring agents from staging or conducting immigration operations on city property, warning that the city would go to court if the use continued.

The letter singled out a Flushing Meadows Corona Park lot near a city-run preschool, describing its use for enforcement as unauthorized, illegal and harmful to residents.

The mayor’s office said agents had reportedly parked vehicles and held meetings at city lots, including at Van Cortlandt Park in the Bronx and Flushing Meadows Corona Park in Queens.

Murad Awawdeh, president and CEO of the New York Immigration Coalition, said five recent incidents involved ICE using parks and parking lots as staging areas to pursue community members.

In response, NYC Parks announced a policy and employee training for handling ICE attempts to access public and non-public areas of park property.

The policy directs staff to refuse requests to use city lots or enter non-public park areas without a warrant, avoid verbal or physical confrontations, and comply with the rules or risk discipline.

Mamdani said Parks staff had been told how to respond and whom to contact if they encounter ICE.

The city is also developing Executive 13 to update agency policies and protocols for non-local law enforcement access to city property.

The Department of Homeland Security defended ICE’s presence in public parking lots as authorized by federal law and standard nationwide, and called on New York to cooperate with federal officers.

Awawdeh said using city parking lots, including Parks Department lots, violates New York’s sanctuary policies, and said he hoped ICE would heed Mamdani’s warning but expected the city might ultimately need to sue.

Gov. Kathy Hochul and Public Advocate Jumaane Williams backed Mamdani, while Queens City Councilwoman Vickie Paladino accused him of overstepping and argued that New York cannot set immigration policy independently of the federal government.