Pakistani officials say U.S. drones fired missiles at a vehicle and house in northwest Pakistan, killing at least 11 militants, including Afghans.

Monday's rare attack in the Kurram tribal region was said to have killed members of the Haqqani network, which has been attacking NATO and Afghan forces in neighboring Afghanistan.

The United States has increased its use of drone strikes against Taliban and al-Qaida militants in Pakistan's northwest tribal areas since the May 2 killing of al-Qaida leader Osama bin Laden — but most of the attacks have been in North and South Waziristan and not Kurram.

The Haqqani network reportedly brokered a deal with local tribesmen in Kurram to allow the militants to cross through the area on the way to Afghanistan and avoid drone strikes in North Waziristan.

U.S. officials have never publicly acknowledged the use of drone strikes against militants in Pakistan. The attacks are a source of friction between the two countries.

On Monday, more than 1,000 tribesmen demonstrated against the drone attacks in Miran Shah, the main town in North Waziristan. The demonstrators shouted “death to America” and vowed to continue their protest until the missile strikes are halted.

Elsewhere in the tribal areas, officials say militants attacked the homes of two anti-Taliban tribal elders in Mohmand, killing at least four people and wounding several others.

Pakistani authorities say one of the elders was wounded in the early Monday attack.

And in the Lower Dir tribal area, police say a young girl wearing a suicide vest was detained at a security checkpoint on Monday. Police say the girl had been kidnapped from the northwestern city of Peshawar and forced to wear the explosives.

In Pakistan's southwest, a car bomb killed at least one person and wounded 12 others Monday on the outskirts of the Baluchistan provincial capital, Quetta.