By Susan Cornwell
WASHINGTON (Reuters) - Turmoil in Yemen and the warnings of attacks that prompted the United States to shut diplomatic missions across the Middle East could hinder President Barack Obama's plans to close Guantanamo Bay prison.
Obama's plan to restart the repatriation of Yemeni inmates, a large group at the prison, is coming under increasing scrutiny because of the recent focus on the country as a hotbed of al Qaeda activity.
A U.S. senator involved in the debate over closing Guantanamo warned against transferring prisoners to Yemen, and an Obama administration official acknowledged that "current conditions will necessarily factor into that evaluation" of whether any detainees should be sent back to Yemen.
"It's not likely to happen" in the near future said Daniel Green, an expert on Yemen at the Washington Institute for Near East Policy.
The prison houses 166 detainees who were rounded up in counter-terrorism operations since the invasion of Afghanistan in 2001. Of those, 86 have been deemed to pose no threat to the United States and cleared for transfer or release. Fifty-six of those are from Yemen, and Obama was expected to begin sending them home soon after he lifted a moratorium on transfers to Yemen in May.
But al Qaeda's regional wing, known as AQAP, keeps raising its head in Yemen, causing concern for U.S. officials who fear that released prisoners could eventually join up with Islamist militants.
"Since it's now well-known that Yemen-based al Qaeda is actively plotting against us, I don't see how the president can honestly say any detainee should be transferred to Yemen," said Senator Saxby Chambliss, the ranking Republican on the Senate Intelligence Committee.
"Sending them to countries where al Qaeda and its affiliates operate and continue to attack our interests is not a solution," Chambliss said in a statement.
Al Qaeda seems to have regrouped since last year when it was driven out of towns in southern Yemen that it had captured.
It is now resorting to hit-and-run operations against senior officers or military installations and the government said on Wednesday it had uncovered a plot to seize two major oil and gas export terminals and a provincial capital in the east of the country.
Yemen has been the main focus of concern that al Qaeda may be planning attacks in August. One of the reasons that the United States closed embassies across the Middle East and Africa was intercepted communication between al Qaeda's Yemen affiliate and al Qaeda's top leadership abroad.
"Al Qaeda is still quite strong in Yemen ... and in general, a fair number of detainees who have been repatriated have rejoined the fight," said Green, of the Washington Institute for Near East Policy.
HUNGER STRIKE EASING
Recent pressure on Obama over Guantanamo has eased slightly as dozens of inmates have come off a hunger strike which peaked earlier this year when more than 100 of the 166 inmates were taking part. Now the number of hunger strikers has dropped to 55.
Obama's promise to close Guantanamo dates back to his first election campaign. But transfers out slowed dramatically in recent years as Congress placed conditions on them. Repatriation of Yemeni prisoners was halted in 2010 after a man trained by militants in Yemen attempted to blow up a Detroit-bound plane in 2009 with a bomb concealed in his underwear.
Chambliss said that Guantanamo detainees who had been released had a "recidivism" rate of 28 percent and that one had been involved in the attacks on the U.S. mission in Benghazi, Libya, last year.
News reports have named Sufyan Ben Qumu, a Libyan who was released from Guantanamo in 2007, as being involved in the assault on the Benghazi mission. A U.S. official told Reuters that Ben Qumu was believed to have participated in the attack, in which four Americans including the ambassador were killed.
Still, Chris Anders of the American Civil Liberties Union, which has urged that Guantanamo be closed, noted that the current detainees who have been cleared for release were approved by every national security agency in the U.S. government.
Yemeni President Abd-Rabbu Mansour Hadi visited Washington last week, hoping to hear some word on when transfers to Yemen would restart. Obama avoided speaking about Guantanamo when the pair appeared in public at the White House.
Hadi is respected in Washington for trying to tackle al Qaeda after taking over in 2012 from long-serving President Ali Abdullah Saleh who stepped down amid protests.
"He's done a heck of a lot, frankly, under some very difficult circumstances," said Green.
(Editing by Alistair Bell and Claudia Parsons)