Mayor Zohran Mamdani warned the Department of Homeland Security on Nov. 2 that New York City will take legal action if Immigration and Customs Enforcement agents keep using city-owned parking lots to stage enforcement operations, in a letter to DHS Secretary Markwayne Mullin and two ICE officials.

The letter says ICE agents have reportedly parked and held meetings in unstaffed city lots, including one at Van Cortlandt Park in the Bronx and lots along 111th Street on the west side of Flushing Meadows Corona Park in Queens, “right next door to a City-run preschool and several cultural institutions that children visit every day.” ICE “has not secured any authorization from the City to use these lots for immigration enforcement,” Mamdani wrote.

“This use of City property in furtherance of federal immigration enforcement is unauthorized and is therefore illegal,” the letter says. It tells the agency it “must immediately issue guidance to your agents prohibiting them from using any City lots to stage or conduct enforcement operations.” The letter, also addressed to acting ICE Director David J. Venturella and ICE New York Field Office Director Kenneth Genalo, does not set a deadline or name a court.