The US military has been using drones armed with missiles in Afghanistan
A missile from a suspected US unmanned aircraft (drone) has killed at least eight people in a Pakistani tribal area close to Afghanistan, reports say.
Unnamed Pakistani security sources say it hit a house in the village of Tappi, North Waziristan, and that the dead include a number of Arabs.
There was no immediate US confirmation of the attack.
Cross-border raids by US forces targeting Islamic militants have strained relations with Pakistan.
Earlier, a roadside bomb exploded close to a prison vehicle and a school bus in north-western Pakistan, killing at least 10 people.
The remote-controlled device exploded in the Upper Dir district of North-West Frontier Province near Swat valley.
Officials said those killed by the blast included four schoolgirls and a number of policemen and prisoners.
Pakistani intelligence sources quoted by Western news agencies differed as to the identity of the owner of the house in Tappi and how many people were killed.
According to some reports, up to nine people were killed in the village, about 20km (12 miles) east of North Waziristan's main town, Miranshah.
At least some of the dead are believed to have been Arabs, possibly militants.
American military commanders blame militants based in the tribal areas for the increase in attacks on coalition forces in Afghanistan.
The latest incident comes a week after a similar bombing in the same region, which killed at least 20 people.
Also on Thursday, a suicide bomb attack on the main police complex in centre of Pakistan's capital, Islamabad, wounded at least 13 people.
Pakistan's parliament has been holding a special session for a classified briefing on Pakistan's internal security situation.
The session was called to try to help form a national consensus on how to tackle Islamic militancy and the surge in suicide bombings.