MIRANSHAH, Pakistan: A US drone aircraft fired missiles into Pakistan’s North Waziristan on the Afghan border on Tuesday, killing up to 10 militants in the second strike in as many days, intelligence officials said.

Although US ally Pakistan is battling militants in its northwest it officially objects to the US strikes by unmanned aircraft, saying they are a violation of its sovereignty and cause civilian casualties.

The latest missile strike came hours after Taleban militants attacked a group of boys on their way to school in another part of the northwest, killing four and wounding three, officials said.

The boys were attacked in the Orakzai ethnic Pashtun tribal region, apparently because they were Shiites. Tribesmen retaliated and killed at least two militants and wounded several, said residents of the area near the region’s main town of Kalaya.

Government aircraft later attacked militants in a village 30 km east of Kalaya, killing six of them and destroying four hideouts, said government official Sajjad Khan.

Pakistani intelligence agents said the target of the missile strike was the house of a cleric near the Afghan border used as a militant hideout.

“Nine to 10 militants have been killed. They are locals affiliated with the Haqqani group,” an intelligence official in the region said referring to veteran Afghan militant commander Jalauddin Haqqani.

Five militants were killed in a similar strike in the same region on Monday. Facing surging violence in Afghanistan, the United States stepped up its missile strikes in Pakistan last year. The drones have killed hundreds of militants since then including the chief of the Pakistani Taleban, Baitullah Mehsud, who was killed in the South Waziristan region early last month.

Pakistani and US officials said the militants were in disarray after Baitullah’s death and their attacks appeared to tail off though they have been picking up again.

Separately, militants set fire to eight container trucks in the southwest carrying supplies for Western forces fighting in Afghanistan, police said.

Foreign forces in land-locked Afghanistan get a significant portion of their supplies, including much of their fuel, trucked in from Pakistan through two border crossings.

In another incident, gunmen kidnapped a Greek man after killing a police guard in the northern Chitral region on the Afghan border, police said. They did not identify the man but said he had been working on a cultural project in the remote Kalash valley since 2001.