The Trump administration must stop its use of California National Guard members in Los Angeles and return control of the troops to the state and Gov. Gavin Newsom, a federal judge in San Francisco ruled Wednesday.

U.S. District Judge Charles Breyer granted a preliminary injunction sought by California officials who opposed an extension of President Donald Trump’s unusual move to use state Guard troops without the governor’s approval. Use of Guard troops is typically granted by the governor at the request of local authorities.

Breyer put his decision on hold until Monday.

California argued that conditions in Los Angeles had changed since Trump first took command of the troops and deployed them in June as immigration enforcement operations ramped up in Southern California. The administration initially called up more than 4,000 California National Guard troops, but that number had dropped to several hundred by late October.

Only 100 or so troops remain in the Los Angeles area, according to the Associated Press.

California officials claimed the administration used isolated incidents of violence in part of downtown Los Angeles during the June immigration enforcement operation protests as a “pretext to federalize” the California National Guard, leading to what California Attorney General Rob Bonta called a months-long military occupation without justification.

“Once again, a court has firmly rejected the President’s attempt to make the National Guard a traveling national police force,” Bonta said in a statement after Breyer’s ruling. “For more than five months, the Trump Administration has held California National Guard troops hostage as part of its political games. But the President is not king. And he cannot federalize the National Guard whenever, wherever, and for however long he wants, without justification. This is a good day for our democracy and the strength of the rule of law.”

The Trump administration extended until February and also tried to use California Guard members in Portland, Oregon as part of its effort to send the military into Democratic-run cities over the objections of mayors and governors.

“The Founders designed our government to be a system of checks and balances. Defendants, however, make clear that the only check they want is a blank one,” the 35-page order signed by Breyer states. “Six months after they first federalized the California National Guard, Defendants still retain control of approximately 300 Guardsmen, despite no evidence that execution of federal law is impeded in any way—let alone significantly. What’s more, Defendants have sent California Guardsmen into other states, effectively creating a national police force made up of state troops.”

U.S. Justice Department lawyers said the administration still needed Guard members in the Los Angeles area to help protect federal personnel and property, such as the federal detention center in downtown LA.

An email to the White House from the Associated Press seeking comment on Wednesday’s ruling was not immediately returned.

Trump took command of the California National Guard following protests over his stepped-up enforcement of immigration laws. The call up was the first time in decades that a state’s national guard was activated without a request from its governor and marked a significant escalation in the administration’s efforts to carry out its mass deportation policy. The troops were stationed outside a federal detention center in downtown Los Angeles where protesters gathered and later sent on the streets to protect immigration officers as they made arrests.

California sued, and Breyer issued a temporary restraining order that required the administration to return control of the Guard members to California. An appeals court panel, however, put that decision on hold.

California argued that the president was using Guard members as his personal police force in violation of a law limiting the use of the military in domestic affairs.

The administration said courts could not second-guess the president’s decision that violence during the protests made it impossible for him to execute U.S. laws with regular forces and reflected a rebellion, or danger of rebellion.

In September, Breyer ruled after a trial that the deployment violated the law. Other judges have blocked the administration from deploying National Guard troops to Portland, Oregon, and Chicago.