WASHINGTON — The Supreme Court on Thursday said the Trump administration must facilitate the return of a Maryland man who was mistakenly deported to El Salvador, rejecting the administration’s emergency appeal.

The court acted in the case of Kilmar Abrego Garcia, a Salvadoran citizen who had an immigration court order preventing his deportation to his native country over fears he would face persecution from local gangs.

U.S. District Judge Paula Xinis had ordered Abrego Garcia, now being held in a notorious Salvadoran prison, returned to the United States by midnight Monday.

“The order properly requires the Government to ‘facilitate’ Abrego Garcia’s release from custody in El Salvador and to ensure that his case is handled as it would have been had he not been improperly sent to El Salvador,” the court said in an unsigned order with no noted dissents.

Chief Justice John Roberts had already pushed back Xinis’ deadline, and the justices said that her order must now be clarified to make sure it doesn’t intrude into executive branch power over foreign affairs, since Abrego Garcia is being held abroad. The court said the Trump administration should also be prepared to share what steps it has taken to try and get him back – and what more it could do.

The administration claims Abrego Garcia is a member of the MS-13 gang, though he has never been charged with or convicted of a crime. His attorneys said there is no evidence he was in MS-13.

The administration has conceded that it made a mistake in sending him to El Salvador, but argued that it no longer could do anything about it.

The court’s liberal justices said the administration should have hastened to correct “its egregious error” and was “plainly wrong” to suggest it could not bring him home.

“The Government’s argument, moreover, implies that it could deport and incarcerate any person, including U. S. citizens, without legal consequence, so long as it does so before a court can intervene,” Justice Sonia Sotomayor wrote, joined by her two colleagues.

In the district court, Xinis wrote that the decision to arrest Abrego Garcia and send him to El Salvador appears to be “wholly lawless.” There is little to no evidence to support a “vague, uncorroborated” allegation that Kilmar Abrego Garcia was once in the MS-13 street gang, Xinis wrote.