A new letter issued by U.S. Attorney General Jeff Sessions’ Justice Department warns so-called “Sanctuary Cities” that they will soon lose federal funding if they refuse to comply with immigration laws.

According to the A.G.’s office, letters have been issued to officials in nine jurisdictions, including New York, Chicago, Las Vegas, Miami, New Orleans, the California Department of Corrections, Philadelphia, and Milwaukee. Each were identified in a May 2016 Inspector General report as having laws that restrict local law enforcement communication with federal immigration officials.

A Justice Department press release said that many of the cities being confronted are “crumbling under the weight of illegal immigration and violent crime.”

“The number of murders in Chicago has skyrocketed, rising more than 50 percent from the 2015 levels,” the release added. “New York City continues to see gang murder after gang murder, the predictable consequence of the city’s ‘soft on crime’ stance.”

In each letter, Acting Attorney General Alan Hanson instructed officials to provide proper documentation by June 30 proving that they are complying with U.S. law. If not, the federal government could withhold, suspend, or terminate their grant dollars. Additionally, cities that refuse to cooperate before the deadline could make themselves ineligible for future funding.

The letters follow an announcement made by Sessions last week, which indicated that a major crackdown on sanctuary city funding would soon happen.

“Such policies cannot continue. They make our nation less safe by putting dangerous criminals back on the streets,” Sessions said in the White House Press Briefing Room. “Today, I am urging states and local jurisdictions to comply with these federal laws.”