"This temporary stay means people detained at airports will not be deported," said the National Immigration Law Center, which had joined with the American Civil Liberties Union and other groups to offer legal aid to those who had been detained - even though they had legal documents to enter the country.
Overnight, the Department of Homeland Security weighed in, saying that while DHS will abide by court orders, the feds will continue to enforce Mr. Trump's new directive.
The fight over the Trump immigration order escalated quickly on Saturday at a number of major airports, as thousands converged on JFK in New York, Dulles outside Washington - as dozens of lawyers arrived to offer their services to families who might have someone caught in immigration limbo.
It resulted in cheering scenes like this when people were released:
The legal fight was also accelerating through the night, as more petitions were made to release people - with legal entry documents - who had been detained at major airports like JFK.
Here are some of the eleven petitions filed from those at JFK:
Part of the legal action came on behalf of Hameed Darweesh, an Iraqi refugee who had assisted the U.S. military in Iraq; he was held at JFK airport outside New York, until being released on Saturday.
More protests were expected through the day on Sunday, as Mr. Trump's immigration order swiftly became an early lightning rod of his administration.