MIAMI - A US federal judge on Thursday barred the Trump administration and Florida state government from bringing any new migrants to the detention centre known as "Alligator Alcatraz" and ordered much of the site to be dismantled, effectively shuttering the facility.
Florida's government swiftly announced it would appeal the decision.
The detention center was hastily assembled in just eight days in June with bunk beds, wire cages and large white tents at an abandoned airfield in Florida's Everglades wetlands, home to a large population of alligators.
President Donald Trump, who has vowed to deport millions of undocumented migrants, visited the center last month, boasting about the harsh conditions and joking that the reptilian predators will serve as guards.
The White House has nicknamed the facility "Alligator Alcatraz," a reference to the former island prison in San Francisco Bay that Trump has said he wants to reopen.
The center was planned to hold 3,000 migrants, according to Homeland Security Secretary Kristi Noem.
But it has come under fire from both environmentalists and critics of Trump's crackdown on migration, who consider the facility to be inhumane.
The new ruling on Thursday by District Judge Kathleen Williams comes after a lawsuit filed against the Trump administration by Friends of the Everglades and the Center for Biological Diversity.
The environmental groups argue that the detention center threatens the sensitive Everglades ecosystem and was hastily built without conducting the legally required environmental impact studies.
US President Donald Trump looks on as Secretary of Defense Pete Hegseth speaks during a cabinet meeting at the White House in Washington, DC, on February 26, 2025. (AFP Photo)