PESHAWAR, Pakistan (Reuters) -- A suspected U.S. drone has fired a missile into a Pakistani Taliban stronghold near the Afghan border, killing at least 14 militants, intelligence officials and residents said.
The United States, grappling with an intensifying Afghan insurgency, began stepping up attacks by pilotless drone aircraft on northwestern Pakistani militant enclaves a year ago despite the complaints of its ally, Pakistan.
The latest attack was in the South Waziristan region, in a stronghold of Pakistani Taliban leader Baitullah Mehsud, the officials and residents said.
"Fourteen militants have been killed and several wounded in the attack that targeted an important compound of Baitullah Mehsud," said Jan Mohammad Mehsud, a resident of the area.
One intelligence agency official said that four or five foreigners were among the 14 people killed, but he had no further information about their identities.
Another intelligence official said that up to 17 people were killed. About 70 militants were killed in a similar strike in the same area last month.
The drone attacks have come as Pakistani troops are slowly preparing for an offensive against Mehsud, carrying out air strikes to soften up targets while soldiers have been sealing off roads into his area.
Mehsud, an Al-Qaeda ally, is accused of orchestrating a campaign of bombings in Pakistan, including the 2007 assassination of former Prime Minister Benazir Bhutto.
The United States has announced a reward of $5 million for information leading to his arrest or location, while the Pakistani government last month posted a reward of 50 million rupees ($615,000) for him.
Pakistan officially objects to the strikes by pilotless U.S. aircraft on its soil, saying they violate its sovereignty and undermine efforts to deal with militancy by inflaming public anger and bolstering support for the militants.
But U.S. officials have said the missile strikes are carried out under an agreement with Islamabad which allows Pakistani leaders to decry the attacks in public.
Residents said that two Pakistani military aircraft flew over the area shortly after the missile strike.
After an alarming expansion of militant influence in northwest Pakistan, the army went on the offensive in Swat two months ago, which U.S. officials welcomed due to fears over Pakistan's stability and the safety of its nuclear arsenal.
The military says it is nearing the end of the offensive in Swat, a former tourist valley northwest of Islamabad, although soldiers are encountering pockets of fighters.
But no Taliban leaders have been among the approximately 1,600 militants the army has reported killed. Independent casualty estimates are not available.
While Pakistan battles the Taliban on its side of the Afghan border, thousands of U.S. Marines have launched an offensive against the Afghan Taliban in the southern Afghan province of Helmand.
Helmand shares a 200-kilometer desert border with the southwestern Pakistani province of Baluchistan.