As promised, President Trump and Attorney General Jeff Sessions are going after sanctuary cities, advising nine of the worst offenders that non-compliance with federal law will see their federal funding cut.

The Trump administration put nine of the country’s top sanctuary cities on notice Friday that they could soon have to give up some federal funds unless they can prove they are no longer thwarting Homeland Security’s efforts to deport illegal immigrants, reports The Washington Times.

The entire state of California is being targeted, as are the cities of New York, Philadelphia, Chicago, Las Vegas, New Orleans and Milwaukee, Wisconsin. Cook County in Illinois and Miami-Dade County in Florida round out the list.

In letters to each of the nine jurisdictions the Justice Department said they signed documents last year, when they applied for Byrne Justice Assistance Grant money, saying they complied with a section of federal law that demands cooperation when immigration agents ask for it.

 “Many of these jurisdictions are also crumbling under the weight of illegal immigration and violent crime,” the Justice Department said as it sent the letters.

Sanctuary cities are those jurisdictions that thwart efforts by deportation officers to kick out illegal immigrants. One common version of a sanctuary policy prohibits local police from alerting federal agents when an illegal immigrant is in custody, or when the illegal immigrant is going to be released. Other versions refuse all contacts.

Without communication, agents are unable to issue or follow through on detainer requests asking that illegal immigrants be held for pickup.