The migrants were deported after Trump invoked the Alien Enemies Act of 1798, which has been used only three times in US history.
The Trump administration has transferred hundreds of immigrants to El Salvador, officials said Sunday, while a federal judge issued an order temporarily halting deportations under an 18th-century wartime declaration targeting Venezuelan gang members, AP reported.
Reports suggest that Boasberg verbally ordered that the planes be returned, but this was not done and he did not include this instruction in his written order.
The migrants were deported after Trump invoked the Alien Enemies Act of 1798, which has been used only three times in US history.
The White House, which has already labelled the Tren de Aragua a terrorist organisation, had prepared to send about 300 suspected members to El Salvador for detention, AP reported.
The Donald Trump administration had agreed to pay El Salvador $6 million to imprison about 300 alleged members of the gang for a year.
Donald Trump on Saturday formally invoked the act granting him wartime powers to target alleged illegal immigration aided by the Venezuelan gang Tren de Aragua.
Trump said, "The result is a hybrid criminal state that is perpetrating an invasion of and predatory incursion into the United States, and which poses a substantial danger to the United States."
On Sunday, White House press secretary Caroline Levitt said the administration was not violating court orders.
"The administration did not ‘refuse to comply’ with a court order. The order, which had no lawful basis, was issued after terrorist TdA aliens had already been removed from US territory," Caroline said.
"A single judge in a single city cannot direct the movements of an aircraft carrier full of foreign alien terrorists who were physically expelled from U.S. soil," she added.
The Justice Department said in its appeal against a judge's order blocking the deportation of five Venezuelans that it would not use Trump's extraordinary act declaration for further deportations if the court's ruling is not overturned, AP reported.
"Oopsie…Too late," Salvadoran President Nayib Bukele, a Trump ally who agreed to house about 300 migrants for a year at a cost of $6 million in his country's prisons, wrote on the social media site X above an article about Boasberg's ruling.
Secretary of State Marco Rubio, who negotiated an earlier deal with Bukele to house migrants, posted on the site: "We sent over 250 alien enemy members of Tren de Aragua which El Salvador has agreed to hold in their very good jails at a fair price that will also save our taxpayer dollars."
Venezuela's government rejected Trump's proclamation of the law in a statement on Sunday, calling it a reminder of "the darkest episodes in human history, from slavery to the horrors of the Nazi concentration camps."
In 1798, with the US preparing for what it believed would be a war with France, Congress passed a series of laws that increased the federal government's reach. Worried that immigrants could sympathise with the French, the Alien Enemies Act was created to give the president wide powers to imprison and deport non-citizens in time of war.
Since then, the act has been used just three times: during the War of 1812, World War I and World War II.
During World War II, with anti-foreigner fears sweeping the country, it was part of the legal rationale for mass internment in the US of people of German, Italian and especially Japanese ancestry. An estimated 1.2 lakh people with Japanese heritage, including those with US citizenship, were incarcerated during the war.