A suicide bomber killed at least 16 other people when he blew himself up in north-western Pakistan.
The attack took place at a military checkpoint to a market in in Khar, the main town in the troubled Bajaur tribal region.
Local officials say a man wearing a vest packed with explosives walked up to the military post and, when he was stopped by soldiers, blew himself up.
The bomber is said to have been heading for government buildings and military barracks. Several vehicles and four shops were destroyed in the bombing.
Officials say two of the dead are Pakistani security officials, and six of the more than 20 injured are in a critical condition.
Hours earlier, nine militants died in a US drone air strike in North Waziristan, local officials said.
Last year, Pakistan's military declared victory over Taliban militants in the district, following a ground offensive, but recently the security situation has been deteriorating.
Close to the Afghan border, Bajaur has long been suspected of being the hiding-place of Osama Bin Laden, Ayman al-Zawahiri and other top al-Qaeda leaders.