Organizers in New York and other major U.S. cities planned to protest outside ICE detention centers, immigration courts and federal buildings on Monday.

The Justice Department on Thursday announced a lawsuit against New York City’s so-called sanctuary city policies, days after the Trump administration blamed those policies for the shooting of an off-duty US Customs and Border Protection officer in Manhattan.

The federal government sued the city last week in an effort to permanently block policies that bar agencies from cooperating with ICE in some instances.