Trump allies and experts say a federal judge overstepped by halting third-country deportations, setting up a legal clash over due process and executive power.

In a chaotic hearing, Trump administration officials told a federal judge they did not know where a plane of deportees was going. The judge raised the possibility that he could order its return.

In a court filing, Trump’s secretary of state claimed blocking migrant deportations to South Sudan will harm efforts to distribute humanitarian aid.

Eight migrant detainees who were on a US flight destined for South Sudan are currently at a US military base in Djibouti, awaiting next steps as details over their case are hammered out in court, two US officials told CNN.

A federal judge in Massachusetts had ordered officials to “facilitate” his return. The United States is still holding a group of other deportees at a base in Djibouti.