WASHINGTON — The United States has sent two Chinese Muslim brothers to Switzerland, ending their eight years of detention at the U.S. naval base at Guantanamo Bay, Cuba.

The Justice Department announced the transfer Wednesday. It did not identify the detainees, but the Obama administration has previously said the Swiss had agreed to resettle two brothers, Arkin Mahmud and Bahtiyar Mahnut.

There are now 183 detainees at Guantanamo, including five Chinese Muslims, or Uighurs. They have been regarded by critics of U.S. detention policies as a symbol of unfairness in the aftermath of the Sept. 11, 2001, terror attacks.

Switzerland’s decision to accept the brothers led the Supreme Court to scuttle a case on detainee rights.