The Anti-Defamation League on Thursday urged a federal court to block US President Donald Trump’s executive order that would withhold funds from from communities that refuse to cooperate with efforts to find and deport immigrants in the country illegally.

In an amicus brief filed with the San Francisco v. Trump case, the ADL said the order “threatens to drive a dangerous wedge between law enforcement and immigrant communities and creates an environment in which victims will be afraid to report crimes, including hate crimes.”

ADL chief Jonathan A. Greenblatt said: “Not only are we are seeing immigrants now afraid to interact with law enforcement, we are also witnessing a concerning spike in hate crimes. If people intent on hurting others know that immigrants will not call the police for help, immigrants will become even more vulnerable. We know that. Sanctuary cities have recognized that. Our hope is that the court sees the danger in this executive order too.”

Other local governments have sued Trump over the “sanctuary cities” issue. Seattle filed a lawsuit against the order on Wednesday. California’s Santa Clara County and two Massachusetts cities with large Latino populations — Chelsea and Lawrence — have also taken legal action.

Alabama Sen. Jeff Sessions, left, looks on as Republican presidential candidate Donald Trump speaks during a national security meeting with advisors at Trump Tower, Friday, Oct. 7, 2016 (Evan Vucci/AP)

Then-Alabama Sen. Jeff Sessions, left, looks on as Republican presidential candidate Donald Trump speaks during a national security meeting with advisors at Trump Tower, Friday, Oct. 7, 2016 (Evan Vucci/AP)

Attorney General Jeff Sessions reiterated this week that the Justice Department would deny grant money to cities that violate a federal law dealing with information-sharing among local police and federal authorities. Sessions said the cities are making their communities unsafe.

The Justice Department said in a statement that “the American people want and deserve a lawful immigration system that keeps us safe and serves our national interest” and that the federal government will enforce relevant laws.

Sessions did not detail what specific factors would trigger the government to deny or strip a city of money, only that it would take “all lawful steps to claw-back” funds already awarded to cities deemed to be out of compliance.

At stake are grants that go toward an array of programs, including victim services, body cameras for police, tools to cut rape kit testing backlogs and police involvement in community events.

In fiscal year 2016, the Office of Justice Programs made nearly 3,000 grants totaling $3.9 billion to cities, counties, states and other local governments.

Although there is no official definition of what makes a locality a “sanctuary,” the Trump administration has begun to publish weekly reports of local jurisdictions that aren’t cooperating with federal efforts to find and deport immigrants in the country illegally, as part of the executive order Trump signed in January.