The first US military aircraft carrying detained migrants to Guantanamo Bay departed on Tuesday, US officials said, as President Donald Trump's administration prepares to potentially house tens of thousands of migrants at the naval base in Cuba.
Trump said he wants the Pentagon and Department of Homeland Security to expand a migrant detention facility at the base to hold more than 30,000 migrants.
US Department of Homeland Security spokesperson Tricia McLaughlin said the military flight to Guantanamo Bay carried 9-10 immigrants.
McLaughlin called them "highly dangerous criminal aliens" but declined to provide further details.
Military flights have already deported migrants to Guatemala, Peru, Honduras and India.
The Pentagon has said it plans to deport more than 5,000 migrants held by US authorities in El Paso, Texas, and San Diego, California.
The military flights are a costly way to transport migrants. Reuters reported that a military deportation flight to Guatemala last week likely cost at least $4,675 per migrant.
Trump has increasingly turned to the military to help carry out his immigration agenda, including sending additional troops to the border, using military aircraft to fly migrants out of the United States, and opening military bases to help house them.
The head of the US Department of Homeland Security on Sunday declined to say whether migrant women, children or families would be held in the Guantanamo Bay detention center.
Homeland Security Secretary Kristi Noem has said the plan was not to hold people at Guantanamo indefinitely and that the administration would follow US law.
The base already houses a migrant facility - separate from the high-security US prison for foreign terrorism suspects - that has been used occasionally for decades, including to hold Haitians and Cubans picked up at sea.
The administration has not said how much it would cost to expand Guantanamo, which was established in 2002 to detain foreign militants in the wake of the 11 September 2001, attacks on the United States.
Its high-security US prison was criticized in 2023 by a United Nations expert, who said the US government's treatment of Guantanamo Bay inmates was cruel, inhuman and degrading under international law. There are 15 detainees left in the prison.
Trump's two Democratic predecessors, Barack Obama and Joe Biden, sought to shut down the Guantanamo prison and were only able to reduce its inmate population, but Trump has vowed to keep it open.
