ISLAMABAD, Pakistan — Three missiles believed to have been fired from American drones killed 15 militants in North Waziristan late Friday night, Pakistani security officials said Saturday. The target of the strike was a compound in the Mamad Khel area of North Waziristan, the officials said.

Four Arab and two ethnic Uzbek fighters were killed, along with local militants, a security official said. Four militants were wounded.

Drone attacks in the region have increased significantly since the Dec. 30 suicide bombing attack at a C.I.A. base in Khost, Afghanistan, which borders Pakistan’s North Waziristan region. Seven Americans and a Jordanian were killed in that attack.

American officials say North Waziristan is the main haven for militants from Al Qaeda and for the Afghan Taliban leader Sirajuddin Haqqani. He is closely allied with the leader of the Pakistani Taliban, Hakimullah Mehsud, who claimed responsibility for the Khost bombing.

Drone attacks are controversial in Pakistan, whose officials argue publicly that the attacks violate their sovereignty. Privately those officials do not oppose the strikes, which many United States officials say have been effective in weakening the Taliban and Al Qaeda by killing many of their senior leaders.

Separately, at least 16 people were killed Saturday and dozens wounded in a suicide attack on a checkpoint in the main market of Khar, the capital of the Bajaur tribal area, according to local residents and Pakistani news reports.

More Articles in World » A version of this article appeared in print on January 31, 2010, on page A12 of the New York edition.