And Murphy has made clear that his staff, which fly into the remote base for hearings and then return to suburban Washington D.C., can prosecute the trials anywhere on U.S. soil. The announcement appeared to quash any speculation that war crimes trials might be held on military bases around the United States.

Separately, officials said they would also use the portion of the Thomson prison used for Guantánamo detainees -- as opposed to federal prisoners -- for indefinite detainees, of whom there were nine approved by the federal courts through habeas corpus review, the yardstick a senior administration official said he would use.

Two senior administration officials, speaking to reporters on condition of anonymity at the insistence of the White House, said current law would allow Guantánamo detainees awaiting military commission proceedings to be transferred to Thomson and would allow the facility to become the new site for those proceedings.

Guantánamo detainees awaiting prosecution through civilian courts would not go to Thomson but to the jurisdiction where they would be tried, such as alleged 9/11 mastermind Khalid Sheik Mohammed and four fellow accused, whom Attorney General Eric Holder have designated for trial in New York. Detainees to be sent to other countries would stay at Guantánamo until leaving the U.S., the officials said.

As for “indefinite detainees,” whom the government likely could not prosecute but who are considered too much of a threat to national security to release, administration officials said they’d need Congress to change the law before they could be transferred to U.S. soil.

Miami Herald staff writer Carol Rosenberg reported from Miami.