Immigration lawyers have asked a federal judge in Massachusetts to prevent the alleged Trump administration from deporting immigrants to a third country, in this case South Sudan.

They also urged federal judge Brian Murphy to immediately order any immigrants who may have been deported back to these "third countries" or they were not originally from these immigrants.

Immigrants from Myanmar, Vietnam and other countries without legal status received notice on Monday that they would be deported.

When lawyers representing detainees tried to contact them on Tuesday, officials at the Isabel Port Detention Center in Texas said at least one person originally from Myanmar had been handed over to South Sudan, according to the attorney’s declaration.

According to documents filed by the U.S. District Court in Massachusetts, “the plaintiff asked the court to order the immediate withdrawal of any class members.” The lawyers also asked the government not to deport immigrants to any country that is not their country of origin unless they receive proper written notice and sufficient time for deportation.

They argue that the Trump administration’s actions to expel clients also violate judicial orders and that there is no proper procedure for prohibiting deportation.

The Department of Homeland Security did not immediately respond to a request for comment.

The Trump administration has been negotiating with people willing to take over the expelled from the United States

The Department of Homeland Security has deported more than 200 Venezuelan immigrants to El Salvador. It argued that some of them were members of the Tren de Alaguya gang and could be deported using the Alien Enemy Act, a vague wartime law that could be quickly removed. The Trump administration also paid El Salvador $6 million to accommodate them.

In early May, the government tried to send migrants to Libya despite human rights groups fearing violence there and the country's infamous human rights record.

South Sudan suffered a prolonged civil war, killing more than 50,000 people until the fragile peace ceased to fight in 2018. Even so, political unrest persists, and conflicts between the rebels and the government continue. Many, including the United Nations, are worried about the prospect of the country falling into a civil war again.