(Muslim Press) - Over 22 mourners have been killed during a procession marking Ashura after an explosion struck the Pakistani province of Sindh on Friday.The explosion also left 30 worshippers wounded, while they were grieving on a Shia religious holiday in the city of Kacobabad. Police sources said that the blast was carried out by a suicide bomber.Recommended:Why Muslims mourn on Ashura day? Over 10,000 extra police officers had been deployed to guard Shia processions during Ashura, according to Al Jazeera. No one has yet claimed responsibility for the incident, but a previous attack by an armed group, Lashkar-e-Jhangvi, was carried out on Thursday. The group has threatened more violence against Shia mourners.