A California judge has issued a preliminary injunction against Border Patrol’s practice of conducting warrantless immigration stops and arrests, denouncing the practice and its alleged targeting of “people with brown skin.”

“You just can’t walk up to people with brown skin and say, ‘Give me your papers,’” U.S. District Judge Jennifer L. Thurston said in court on Monday ahead of her ruling, according to Cal Matters.

Her order, which was signed on Tuesday, states that Border Patrol agents must abide by federal law while conducting stops throughout the Eastern District of California, which includes Fresno, Sacramento, Bakersfield, Redding and Yosemite.

This means there must be reasonable suspicion of illegal presence to stop someone, as required under the Fourth Amendment. Arrests must also involve a warrant unless there’s probable cause to believe that a person is likely to escape before a warrant can be obtained.

Thurston’s order follows the American Civil Liberties Union filing a lawsuit against the Department of Homeland Security and U.S. Border Patrol in February after federal agents were accused of breaking car windows and slashing tires to detain and arrest individuals, including a U.S. citizen, over several days in Kern County, which includes Bakersfield.

The lawsuit, filed on behalf of United Farm Workers, alleges that agents participating in a sweep dubbed “Return to Sender” specifically targeted people of color who appeared to be farmworkers or day laborers, “regardless of their actual immigration status or individual circumstances.”

“The person’s perceived race, ethnic background, or occupation cannot justify a detentive stop. Nor can a person’s refusal to answer voluntary questions,” the suit states.

Some of the people stopped or taken into custody said they were subjected to unjustified traffic stops or arrested by plainclothed agents while standing outside a Home Depot store. They said that Border Patrol agents, without identifying themselves, demanded they produce identification and “papers.” One man said he was placed in handcuffs when he ignored the questioning and tried to walk away, according to the lawsuit.

Thurston’s order will remain in place as the case proceeds.

DHS Assistant Secretary Tricia McLaughlin said the Trump administration “is committed to restoring the rule of law to our immigration system” in a statement to HuffPost on Wednesday.

“No judge, not this one or any other, is going to stop us from doing that,” McLaughlin said.

In earlier filings, attorneys representing DHS argued that “public interest should favor an agency taking prompt, responsive action in light of a complaint against it.” They also argued that the majority of the people cited in the complaint as having been detained or arrested were ultimately found to be in the country illegally. Efforts are also already underway to retrain officers to prevent warrantless arrests, they said.