A suicide bombing has ripped through a protest rally in Pakistan, killing at least 13 people and wounding 58.
Jamaat-ul-Ahrar, a Taliban breakaway faction, have claimed responsibility for the bombing in Lahore in the east of the country.
A local police official said the bombing targeted a group of police escorting hundreds of pharmacists who were protesting over new amendments to a law governing drug sales.
Zaheer Abbas continued that six police officers, including a former provincial counter-terrorism chief, were among those killed.
Nine of the injured are reported to be in critical conditions.
Live TV registered a loud bang and showed smoke and fire billowing up as people ran away, some of them carrying the wounded.
"We just couldn't understand what happened," Tufail Nabi - a witness at the scene - told local media.
"It was as if some big building collapsed," he added.
Jamaat-ul-Ahrar claimed the attack in a text message, saying it was revenge for Pakistani military operations against Islamic militants in tribal regions along the Afghan border.