Prisoners escape U.S. base in Afghanistan

Four prisoners escaped on Monday from a detention centre at the main U.S. military base in Afghanistan, the U.S. army said.

Military spokesman Lieutenant-Colonel Jerry O'Hara said the men escaped from the Bagram air base, north of Kabul, at about 5 a.m. (0030 GMT).

"We have an ongoing operation to recover four individuals who escaped from our detention facility," he said, describing the detainees as "dangerous enemy combatants".

O'Hara said that there had been no U.S. casualties during the escape, and that there had been no reports of violence or any U.S. staff missing.

"I can't give specifics on how they escaped," he said. "The circumstances surrounding the escape are under investigation as we speak."

Afghan sources said all four escaped prisoners are Arabs, but O'Hara refused to comment.

One correspondent in Kabul says the escape is the first from the heavily fortified detention centre, and is a major embarrassment for the U.S. army.

The detention centre in Bagram has housed hundreds of people, including many Afghans, detained by the U.S. since it invaded Afghanistan in late 2001.

A U.S. army spokeswoman said last week that over 450 suspects are being held at Bahram.