■ A federal judge halted the use of a health order to expel migrant families.

WASHINGTON — A federal judge ruled Thursday that the U.S. government must stop using a Trump-era public health order to quickly expel migrants with children who are apprehended along the U.s.-mexico border.

U.S. District Judge Emmet Sullivan gave the government two weeks to halt a practice that opponents say is unnecessary and improperly relies on the threat posed by COVID-19 to deprive people of their right to seek asylum in the United States.

Sullivan granted a preliminary injunction in response to a lawsuit filed by the American Civil Liberties Union and others on behalf of migrant families, saying they were likely to succeed in their challenge to the use of the public health law known as Title 42.

The Biden administration was evaluating the ruling and had no immediate comment on whether it plans to appeal.

Title 42 was invoked early in the pandemic, under President Donald Trump, ostensibly to help control the spread of COVID-19 in detention facilities by turning back migrants encountered by Border Patrol without giving them a chance to seek to stay in the U.S. by asking for asylum or for some other reason.

President Joe Biden halted the practice of expelling children crossing by themselves, following reports that they were being sent alone into dangerous Mexican border cities but continued turning away most other migrants.

In recent months, Mexico has begun accepting fewer migrant families with children and the U.S. has been allowing some to remain in the country as they seek to stay.