New York Gov. Andrew Cuomo (D) on Wednesday issued a cease-and-desist letter to U.S. Immigration and Customs Enforcement (ICE), saying the agency uses “aggressive tactics” to make illegal arrests.

The Washington Post reported Thursday that Cuomo accused the agency of storming private properties without warning, without identifying themselves and without a warrant to make any arrests.

Cuomo, during a press conference, cited possibly illegal arrests at a dairy farm and private residence. He also noted an outspoken immigration activist that was also taken into custody.

If the agents keep making arrests in this manner, Cuomo warned that “the state will sue them, period.”