DNA tests have confirmed that a man shot and killed by British forces in Iraq was the leading al-Qaida terrorist who embarrassed the US military by making an unprecedented escape from a maximum-security military prison in Afghanistan, the US command said today.

Security has been tightened at a massive US military detention facility in Afghanistan, a US official said today, a day after the military revealed that one of four men who escaped in July was a suspected al-Qaida leader in Southeast Asia.

US authorities were yesterday interrogating the newly-captured chief of al-Qaida operations in the Persian Gulf.