Dozens of released Guantanamo detainees have returned to the battlefield, said a senior US Senator, urging the Barack Obama administration not to release more inmates from the war-on-terror prison camp.

US Senator Dianne Feinstein told CBS television's "Face the Nation" program that about a third of former inmates at the US naval base who have returned to fight against US interests come from Yemen, the new focal point in the US fight against terrorism.

"If you look at Yemen, and we're taking a good look at Yemen, what you see is I think at least 24 or 28 are confirmed returned to the battlefield in Yemen, and a number are suspected," said Feinstein, head of the Senate Intelligence Committee.

"If you combine the suspected and the confirmed, the number I have is 74 detainees have gone back into the fight, and I think that's bad," she said.

Closing Guantanamo: a numbers game

"I think the Gitmo experience is not one that leads to rehabilitation," Feinstein added.

Her views were seconded by Congressman Peter Hoekstra, the top Republican on the House Intelligence Committee, who appeared on the same CBS television program.

"These people are released and a number of them go back to the battlefield," he said.

"When these Gitmo detainees find their way back on the battlefield, they're no longer focused on the conflict in Pakistan, Afghanistan or Iraq," he said.

"They form the corps of people who want to attack the United States. It's a national security, homeland security issue."

Their remarks came just days after a Pentagon spokesman confirmed that an increasing number of former detainees from the US prison in Guantanamo have forged links to militant groups after their release.

Spokesman Geoff Morrell told reporters last week that the precise number remained classified, but was in keeping with an April Defense Department report in April that found that about 14 percent of former Guantanamo inmates had engaged in or were suspected of having ties to militants.

The issue has taken on heightened importance after a failed attack on a US airliner on Christmas Day was tied to Al-Qaeda's branch in Yemen, where two former Guantanamo detainees are believed to be acting as senior leaders.

President Barack Obama on Tuesday suspended transfers of Guantanamo detainees to Yemen following the Christmas Day incident.

The administration remains under intense pressure however from domestic critics not to release any of the remaining 198 detainees at Guantanamo, which include includes an estimated 91 Yemenis, amid rising fear in the United States regarding terrorism.

This video is from CBS' Face the Nation, broadcast Jan. 10, 2010.

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