Washington’s police department chief said that a Trump administration order installing a federal official as its head would upend command structure and be a “dangerous” threat to law and order. Police Chief Pamela Smith’s statement came in a court filing as the city seeks to block the federal takeover of its police department in court.

Washington’s top legal official sought an emergency restraining order in federal court blocking a Trump administration move to put a federal official in charge of its police. District of Columbia Attorney General Brian Schwalb argues the police takeover is illegal and threatens to “wreak operational havoc.”

The lawsuit comes after U.S. Attorney General Pam Bondi said Thursday night that Drug Enforcement Administration boss Terry Cole will assume the police chief’s duties and approval authority for any orders issued to officers. It was unclear where the move left the city’s current police chief, Smith, who works for the mayor.

Schwalb argues the new order goes beyond Trump’s authority and implementing it would “sow chaos” in the Metropolitan Police Department. “The administration’s unlawful actions are an affront to the dignity and autonomy of the 700,000 Americans who call D.C. home. This is the gravest threat to Home Rule that the District has ever faced, and we are fighting to stop it,” Schwalb said.

The Justice Department declined to comment on the district’s lawsuit, and a White House spokesperson did not immediately respond to messages seeking comment Friday morning.

The police takeover is the latest move by Trump to test the limits of his legal authorities to carry out his agenda, relying on obscure statutes and a supposed state of emergency to bolster his tough-on-crime message and his plans to speed up the mass deportation of people in the United States illegally.

It also marks one of the most sweeping assertions of federal authority over a local government in modern times. While Washington has grappled with spikes in violence and visible homelessness, the city’s homicide rate ranks below those of several other major U.S. cities, and the capital is not in the throes of the public safety collapse the Trump administration has portrayed.

Chief had agreed to share immigration information

Schwalb had said late Thursday that Bondi’s directive was “unlawful,” arguing it could not be followed by the city’s police force. He wrote in a memo to Smith that “members of MPD must continue to follow your orders and not the orders of any official not appointed by the Mayor,” setting up the legal clash between the heavily Democratic district and the Republican administration.

The district’s attorney general is an elected position and the city’s top legal officer. It’s separate from federal U.S. attorney appointed by the president to serve in Washington, a role now filled by former Fox News Channel host and judge Jeanine Pirro. Trump also appointed Bondi as U.S. attorney general, the nation’s top law enforcement official.

Bondi’s directive came even after Smith had told MPD officers hours earlier to share information with immigration agencies regarding people not in custody, such as someone involved in a traffic stop or checkpoint. The Justice Department said Bondi disagreed with the police chief’s directive because it allowed for continued enforcement of “sanctuary policies,” which generally limit cooperation by local law enforcement with federal immigration officers.

Bondi said she was rescinding that order as well as other MPD policies limiting inquires into immigration status and preventing arrests based solely on federal immigration warrants. All new directives must now receive approval from Cole, the attorney general said.

Washington Mayor Muriel Bowser pushed back Thursday, writing on social media that “there is no statute that conveys the District’s personnel authority to a federal official.”

The president has more power over the nation’s capital than other cities, but D.C. has elected its own mayor and city council since the Home Rule Act was signed in 1973.

Trump is the first president to exert control over the city’s police force since it was passed. The law limits that control to 30 days without congressional approval, though Trump has suggested he’d seek to extend it. Schwalb argues the president’s role is narrow under the law, limited to requiring the mayor to provide police services for federal purposes.

Residents are seeing a significant show of force

A population already tense from days of ramp-up has begun seeing more significant shows of force across the city. National Guard troops watched over some of the world’s most renowned landmarks and Humvees took position in front of the busy main train station. Volunteers helped homeless people leave long-standing encampments — to where was often unclear.

Department of Homeland Security police stood outside Nationals Park during a game Thursday between the Washington Nationals and the Philadelphia Phillies. DEA agents patrolled The Wharf, a popular nightlife area, while Secret Service officers were seen in the Foggy Bottom neighborhood.

Bowser, walking a tightrope between the Republican White House and the constituency of her largely Democratic city, was out of town Thursday for a family commitment in Martha’s Vineyard but would be back Friday, her office said.

The uptick in visibility of federal forces around the city, including in many high-traffic areas, has been striking to residents going about their lives. Trump has the power to take over federal law enforcement for 30 days before his actions must be reviewed by Congress, though he has said he’ll re-evaluate as that deadline approaches.

Officers set up a checkpoint in one of D.C.’s popular nightlife areas, drawing protests. Troops were stationed outside the Union Station transportation hub as the 800 Guard members who have been activated by Trump started in on missions that include monument security, community safety patrols and beautification efforts, the Pentagon said.

Troops will assist law enforcement in a variety of roles, including traffic control posts and crowd control, National Guard Major Micah Maxwell said. The Guard members have been trained in de-escalation tactics and crowd control equipment, Maxwell said.

National Guard troops are a semi-regular presence in D.C., typically being used during mass public events like the annual July 4 celebration. They have regularly been used in the past for crowd control in and around Metro stations.