A bomb attack targeting police has killed at least 20 people in Pakistan's northwestern tribal district along the Afghan border, officials say.
A suicide bomber targeting a paramilitary vehicle struck near a crowded street market in the town of Khar in the Bajur Agency region on Friday morning.
Eight security forces personnel are among the dead, officials said.
The Pakistani Taliban claimed responsibility for the attack, which a spokesperson for the group said was aimed at Fazal Rabi, a security officer who was given a presidential award for his role in fighting the Taliban.
Rabi was among those killed in the blast, government administrator Abdul Haseeb confirmed on Friday.
Al Jazeera's Kamal Hyder, reporting from the Pakistani capital Islamabad, said that at least 40 people who were wounded had been rushed to the local hospital where an emergency was declared.
"The suicide bomber is said to have attacked a security post in a busy time in the morning when people were going around doing their ordinary things.
"The suicide bomber is then said to have detonated his device, killing a few security forces personnel including a highly decorated officer who was recently given a presidential award for his fighting against the Taliban.
"There were innocent passerbys who were also caught by the blast," Hyder said.
Police and security forces sealed off the site of the attack. Reports said that school children were among those wounded, and health officials said they expected the death toll to rise.
The Pakistani Taliban have carried out similar attacks in the past.
Friday's blast came two days after Pakistan went on a high state of alert for the first anniversary of Osama bin Laden's killing by American troops, fearing a wave of revenge attacks.
Khar is the main town in the Bajur tribal region, bordering Afghanistan, where Pakistan has carried out operations against local Taliban.