President Donald Trump on Thursday confirmed that a group of migrants from countries including Vietnam, Cuba and Mexico were stuck in the East African nation of Djibouti on their way to being deported to South Sudan, a location U.S. officials had previously said in court was classified.

The revelation, made by the president in a social media post, came as the legal fate of the eight men remained uncertain and their exact whereabouts unknown. A lawyer for some of the migrants said she was concerned for their welfare.

In a sharp rebuke of the government Wednesday, a federal judge in Boston found the deportation of the men from Texas a day earlier violated an order he issued last month requiring that immigrants receive reasonable notice before being deported to a country not their own. Lawyers for some of the migrants, who had rushed to U.S. District Court in Boston to challenge their deportations, said they had been told they were headed to South Sudan, a country teetering on the brink of civil war.

Trump administration officials refused to confirm in open court where the men were being sent, describing the information at one point as “classified” and later as “sensitive.” On Wednesday morning, Tricia McLaughlin, a spokesperson for the Department of Homeland Security, also declined to tell reporters the location of the plane or where it was headed, citing “operational security.”

Amid the legal wrangling, the flight carrying the migrants landed in Djibouti, as The New York Times previously reported. It remained unclear where they were being held and under what conditions.

The judge, Brian E. Murphy, said Wednesday that Trump officials had given the deportees “plainly insufficient” time to contest their expulsion. He directed the administration to provide the deported men the opportunity to contest their removal from the United States on the ground in Djibouti.

But while those interviews were taking place, he said, officials from U.S. Immigration and Customs Enforcement had to maintain custody over them. On Thursday, Trump assailed that decision.

“A Federal Judge in Boston, who knew absolutely nothing about the situation, or anything else, has ordered that EIGHT of the most violent criminals on Earth curtail their journey to South Sudan, and instead remain in Djibouti,” the president said on his social media site. “He would not allow these monsters to proceed to their final destination.”

Documents provided by DHS showed that the eight men were citizens of Cuba, Laos, Mexico, South Sudan, Myanmar and Vietnam, and had been convicted of crimes including murder, sexual assault and robbery.

In an interview Thursday afternoon, Trina Realmuto, a lawyer for some of the migrants, said she and her colleagues had not yet been in touch with the detainees and had not heard from the government about when access would be provided.

“The judge ordered that the individuals have access to counsel; we are still waiting for the government to provide that access,” said Realmuto, executive director of the National Immigration Litigation Alliance. “We are increasingly concerned for their health and welfare. We expect that we will hear from them, but we have not yet.”