A new report estimates that one-fifth of the detainees who have been released from the U.S. military prison at Guantanamo Bay, Cuba, have resumed extremist activity, a Defense Department official said Wednesday, a figure that intensifies the debate over the prison.

The Pentagon report on the released detainees remains classified and officials refused to discuss it publicly. But Pentagon Press Secretary Geoff Morrell acknowledged the numbers had risen since April, when the department said about 74 former detainees -- about 14% of those released -- had returned to hostile action against the United States.

The Pentagon method for counting former detainees who once again have taken up arms remains contentious. Conservatives argue that it undercounts the number of terrorists who have returned to the battlefield, whereas liberals say previous lists were inflated and included detainees who were wrongly arrested or were involved in local, not international, disputes.

The new estimate comes on the heels of an announcement by the Obama administration that it would halt Guantanamo transfers to Yemen. Republicans are pushing for a more expansive moratorium -- in particular, demanding that the U.S. stop sending detainees to Saudi Arabia.


President Obama last year ordered the Guantanamo Bay detention center closed, but the shutdown -- which was to have occurred by this month -- was postponed when the administration encountered difficulties in sending detainees back to their home countries or transferring them elsewhere.

Obama wants to send the remaining detainees to a prison in Thomson, Ill., the site of a state prison that the administration would like to purchase and operate as a federal prison and military detention center.

The George W. Bush administration released an estimated 500 detainees from Guantanamo Bay. Obama has transferred several dozen.

Senior members of Al Qaeda in the Arabian Peninsula, the group that claimed responsibility for the attempted Christmas Day bombing of a U.S.-bound jetliner, are former detainees at Guantanamo, including Saeed Ali Shahri, a Saudi who is the group’s second-in-command.


White House Press Secretary Robert Gibbs said Wednesday that he didn’t know if the decision to halt repatriation of Yemeni detainees had anything to do with the perceived likelihood that they would join up with extremist organizations.

“We never have a plan to transfer anybody either to a home country or to a third country that we have reason to believe will present a security situation for us or for that country,” Gibbs said.

Human rights organizations and lawyers for some of the detainees believe the Pentagon’s recidivism statistics are inflated.

“I take a jaundiced view of those numbers,” said attorney Marc Falkoff, whose clients include Guantanamo detainees. “They don’t identify the recidivists or what they did wrong.”


Although human rights groups have not seen the new Pentagon report, several reviewed the list released in April. At least two people were placed on that list for making statements critical of the U.S., critics said. Another was classified as a recidivist after being arrested for allegedly being involved in an uprising in the predominantly Muslim town of Nalchik, in southern Russia.

“A guy who was beaten up by the Russians for participating in an armed rebellion -- that is not tantamount to returning to the battlefield to fight Americans,” said Stacy Sullivan, a counter-terrorism advisor with Human Rights Watch.

But Charles Stimson, a scholar at the conservative Heritage Foundation, criticized the Pentagon list for not including more names.

“Why is it that nobody is surprised that career criminals have a recidivism rate above 90%, yet people act with shock and disbelief when committed jihadists have a recidivism rate of 20%?” Stimson said.


Stimson, a former deputy assistant secretary of Defense for detainee operations in the Bush administration, added, “I have every reason to believe it is very conservative and the actual number is substantially higher than 20%.”

julian.barnes@latimes.com

cparsons@latimes.com