A bomb blast in Pakistan's north-west city of Peshawar has killed at least 14 people - mostly policemen including two senior officers - officials say.
It is not yet clear who was the intended target of the blast
At least 30 others were injured by the explosion just as a Shia religious procession was about to start.
Initial indications point to a suicide bombing, officials say.
This is the second deadly blast in Pakistan in two days. On Friday, a suicide bomber blew himself up at an Islamabad hotel, also killing a guard.
Peshawar chief of police Malik Saad and the city's deputy superintendent were among the dead.
Security forces have been on high alert ahead of the annual Shia festival of Ashoura, commemorating the 7th Century martyrdom of the Prophet Muhammad's grandson.
In recent years Sunni extremists have targeted Shias during this period, says the BBC's Barbara Plett in Islamabad.
There have also been threats of retaliation following government strikes against militants in the nearby tribal areas.
'In a bad way'
Most of the victims were police and municipal officials clearing the route for a Shia procession, officer Aziz Khan - who was on duty nearby - told AP news agency.
"I was shocked by a big explosion. I thought my eardrums had burst. Then there were flames and the people were in panic.
Troops have been on high alert ahead of a Shia religious festival
"I remembered that there was a police contingent, so I went to see what had happened to my colleagues. Many were wounded in a bad way," he said.
Blood and flesh were splattered over the narrow lane where the blast took place, and there was broken glass from shop fronts underfoot as police scoured the site, Reuters news agency said.
It is not clear whether the attack was aimed at the worshippers or the police.
Power was cut in the city centre shortly after the blast, complicating rescue efforts.
Hundreds of people rushed to hospitals, hoping for news of their loved ones.
President Pervez Musharraf strongly condemned the attack and expressed condolences to the victims' families.