WASHINGTON (AFP) - Al-Qaedas core leadership has been severely damaged but the networks affiliate has exploited unrest in Yemen and poses a growing danger, US intelligence chiefs said Tuesday. Even as Al-Qaeda faces unprecedented pressure, its Yemen-based branch has emerged as the most dangerous regional node in the global jihad and has benefited from turmoil in Yemen, the new CIA director David Petraeus told lawmakers. The CIA assesses that, 10 years after the 9/11 attacks, the United States continues to face a serious threat from Al-Qaeda and its worldwide network of affiliates and sympathisers, said Petraeus, the countrys most prominent general who retired from the military to take over the CIA job. Heavy losses among Al-Qaedas leadership have created an important window of vulnerability for the network in Pakistan and Afghanistan, but exploiting that window will require a sustained, focused effort, he said. At the same time, the extremist initiative is, to some degree, shifting to Al-Qaedas affiliates outside South Asia, Petraeus said. Since May, Yemen-based Al-Qaeda in the Arabian Peninsula (AQAP) has pushed back Yemeni government forces in the south and political upheaval has helped AQAP co-opt local tribes and extend its influence, he said. At the same hearing, National Intelligence Director James Clapper said Al-Qaeda in Yemen was clearly a determined enemy, citing the groups attempts to blow up a US-bound airliner in December 2009 and cargo planes in October last year. We have substantial concerns about this groups capability to conduct additional attacks targeting the US homeland and US interests overseas, as well as its continuing propaganda efforts designed to inspire like-minded Western extremists to conduct attacks in their home countries, Clapper said. Petraeus also said Al-Qaedas affiliates in southeast Asia and Somalia had suffered setbacks with senior figures now dead. The two appeared before a joint hearing of the Senate and House intelligence committees, the first in 10 years, looking at the state of US spy agencies in the decade since the September 11, 2001 attacks. Both men cited the killing of Al-Qaeda leader Osama bin Laden in a US raid in May as a major blow to the terror network and described it as a product of increasing cooperation among intelligence agencies and the military. Clapper said the spy services have made dramatic progress in the past 10 years in sharing information, which was seen as a major failing before 9/11. With Congress preparing for difficult budget cuts, Clapper said the intelligence agencies were looking at where they could find savings without jeopardising vital security work. But he said some capabilities would have to be sacrificed due to budget cuts, without specifying what tasks he had in mind.