Washington, March 18 (IANS) The US Central Intelligence Agency (CIA) believes Osama bin Laden and his top deputy, Ayman al-Zawahiri, are inside Pakistan though it does not know precisely where.

The agency officials believe the two are hiding, "either in the northern tribal areas or in North Waziristan, or somewhere in that vicinity," CIA Director Leon Panetta told The Washington Post in an interview published Thursday.

While there have been no confirmed sightings of either man since 2003, the continued pressure on Al Qaeda increases the opportunities for catching one or both, he said.

Relentless attacks against Al Qaeda in the Pakistan tribal region appear to have driven bin Laden and other top leaders deeper into hiding, leaving the organization rudderless and less capable of planning sophisticated operations, Panetta told the Post.

So profound is Al Qaeda's disarray that one of its lieutenants, in a recently intercepted message, pleaded to bin Laden to come to the group's rescue and provide some leadership, Panetta claimed.

In what the post called a near-acknowledgement of the CIA's war against extremists in Pakistan, Panetta credited an increasingly aggressive campaign against Al Qaeda and its Taliban allies, including more frequent strikes and better coordination with Pakistan.

Calling it "the most aggressive operation that CIA has been involved in in our history," he said, "Those operations are seriously disrupting Al Qaeda."

"It's pretty clear from all the intelligence we are getting that they are having a very difficult time putting together any kind of command and control, that they are scrambling. And that we really do have them on the run."

Panetta also cited recent arrests of top Taliban figures-mostly notably Mullah Abdul Ghani Baradar, captured in Karachi on Feb 8, as tangible evidence of improving ties with Pakistan's intelligence service. He told the Post Pakistan had given the CIA access to Baradar since his capture, and added, "we're getting intelligence" from the interrogation.

Panetta acknowledged that Al Qaeda was continuing to look for ways to kill Americans and was specifically seeking to recruit people who lacked criminal records or known ties to terrorist groups to carry out missions.

Still, the CIA under the Obama administration is "without question putting tremendous pressure on their operation," Panetta said.

"The president gave us the mission to disrupt, dismantle and defeat Al Qaeda and their military allies and I think that's what we are trying to do."