BARA, Pakistan  More than 70 United States military advisers and technical specialists are secretly working in Pakistan to help its armed forces battle Al Qaeda and the Taliban in the country’s lawless tribal areas, American military officials said.

The Americans are mostly Army Special Forces soldiers who are training Pakistani Army and paramilitary troops, providing them with intelligence and advising on combat tactics, the officials said. They do not conduct combat operations, the officials added.

They make up a secret task force, overseen by the United States Central Command and Special Operations Command. It started last summer, with the support of Pakistan’s government and military, in an effort to root out Qaeda and Taliban operations that threaten American troops in Afghanistan and are increasingly destabilizing Pakistan. It is a much larger and more ambitious effort than either country has acknowledged.

Pakistani officials have vigorously protested American missile strikes in the tribal areas as a violation of sovereignty and have resisted efforts by Washington to put more troops on Pakistani soil. President Asif Ali Zardari, who leads a weak civilian government, is trying to cope with soaring anti-Americanism among Pakistanis and a belief that he is too close to Washington.