US intelligence will pursue operations aggressively: Leon Panetta

US intelligence has caused "exceptionally heavy damage" to Al Qaeda and the CIA intends to continue counter terrorism operations "aggressively" in South Asia, according to the agency's top ranking official.

Strongly defending the US spy service against criticism following a suicide bombing in eastern Afghanistan in which seven CIA operatives were killed, Leon Panetta the agency director said, "We intend to push forward the work we do in the region".

"We have done exceptionally heavy damage to Al Qaeda and its associates. That's why the extremists hit back. And it is all the more reason why we intend to stay on the offensive", Panetta wrote today in an op-ed piece in Washington Post.

His comments come after sharp reactions to a Jordanian doctor, said to be a triple agent blowing himself up at the US intelligence-cum-military base near the Pakistani border on December 30, the deadliest attack against the CIA since the Beirut bombing of 1983.

The Al Qaeda as well as the Taliban hailed the suicide bombing as a revenge for the slaying of number of their top commanders in US drone strikes in Pakistan.

Rebutting criticism that safety procedures were ignored in allowing the Jordanian human bomber access to the top secret forward operating base Chapman in Khost province in eastern Afghanistan, Panetta said, "The individual was about to be searched by our security officers--- a distance away from other intelligence personnel--- when he set off his explosives".