At least 27 people have been killed and more than 40 others wounded after a suicide bomber detonated his explosives outside a mosque in northwest Pakistan, police say.
The explosion in Hangu town happened as worshippers were leaving the mosque after Friday prayers.
The bomber staged his attack at one of the mosque's exits leading to a bazaar, said Hangu police chief Mian Mohammad Saeed.
"It was a suicide attack which targeted Shias but Sunni Muslims also fell victim since their mosque and some shops were also very close to the site," he told the AFP news agency.
"We have found the head of the bomber, who came there on a motorbike."
The blast damaged several small shops and peppered a wall with shrapnel, leaving scores of pockmarks, according to local TV footage. Ambulances rushed in to pick up the dead and wounded, as police tried to keep back onlookers in
the crowded bazaar.
The most seriously wounded were taken to the Lady Reading Hospital in Peshawar, the provincial capital, reported Al Jazeera's Kamal Hyder from Islamabad.
There was no immediate claim of responsibility for the attack.
Hangu has experienced conflict in the past between the Sunni and Shia communities that live in the town. Both sides have attacked each other's shops and burned them.
"The Shia and Sunni mosques are very close to each other, and the explosion took place just as Shias were coming out of the mosque and Sunnis were going into their mosque to say Friday prayers," said police official Imtiaz Shah.
The town in Khyber Pakhtunkhwa province is close to Pakistan's semi-autonomous tribal belt on the Afghan border where Taliban and al-Qaeda-linked fighters have carved out strongholds.
Shias make up an estimated 20 percent of Pakistan's population of 180 million.
Human Rights Watch says it documented a sharp escalation in persecution of religious minorities in Pakistan in 2012, which it called the deadliest year on record for Shias, with well over 400 killed in targeted attacks.
Activists accuse the government of failing to protect Shias and say the perpetrators operate with impunity because the judiciary fails to prosecute them.