About one in five ex-detenus has engaged in, or is suspected of engaging in, terrorism or militant activity.

Administration officials said on Wednesday that a classified Pentagon report concludes that of some 560 detenus transferred abroad from the military prison at Guantanamo Bay, about one in five has engaged in, or is suspected of engaging in, terrorism or militant activity.

The finding comes amid reports that one former Guantanamo detenu released in 2007 under the administration of President George W. Bush is now involved in al-Qaeda in the Arabian Peninsula, a group that President Barack Obama has said sponsored the attempt to bomb an American airliner on Christmas Day.

Mr. Obama announced on Tuesday that he was suspending the transfers of additional detenus from Guantanamo to Yemen, even though he said he remained committed to his plan, now delayed, to close the prison.

A Pentagon report released last May found that about one in seven of the 534 prisoners who had been transferred had engaged in terrorism or militant activity or was suspected of doing so.

Geoff Morrell, the Pentagon press secretary, would not confirm the findings in the most recent Pentagon report, but he said on Wednesday at a briefing that “the trend hasn’t reversed itself.” He said that determining which Guantanamo detenus should be released was an “inexact science” and that officials were “making subjective calls based upon judgment, intelligence, and so there is no foolproof answer in this realm.”

Civil liberties and human rights groups sharply criticised the May 2009 report and earlier Pentagon reports during the Bush administration concluding that substantial numbers of former Guantanamo detenus had engaged in terrorism or militant activity. The groups said that the information was too vague to be credible and amounted to propaganda in favour of keeping the prison open.

In the May report, the Pentagon said that 74 former prisoners were engaged in or suspected of engaging in terrorism or militant activity, but it identified only 29 of them by name. Of those, many were described as associating with terrorists or training with terrorists, with few other details provided. The Pentagon provided no way of authenticating the 45 unidentified former detenus.

The Obama administration has been highly sensitive to Republican criticism that it is soft on terrorism and has sought to distance itself from the decisions to release Guantanamo detenus during the Bush administration.

Mr. Obama inherited 242 detenus at Guantanamo when he took office, and so far he has released or transferred 44. Of the 198 remaining, about 92 are from Yemen. Of those, just under 40 have been cleared for release.

An administration official said that the White House had “been presented with no information that suggests that any of the detainees transferred by this administration have returned to the fight.” The official was critical of the Bush administration for what the official said was a sloppy, ad hoc process for determining which detenus would be released.

Mr. Obama’s decision to suspend the transfers of detenus from Guantanamo to Yemen was another reflection of his difficulties in closing the prison.

The President was already on track to miss his self-imposed one-year deadline for closing the prison by January 22, but evidence that the Qaeda branch in Yemen was behind the attempted airliner attack on December 25 means he will probably fall further behind schedule. — © 2010 The New York Times News Service

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