At least seven people were killed and over a dozen wounded in an explosion at a Shiite mosque in southern Afghanistan during Friday prayers, a hospital official said. It was not immediately clear what caused the explosion, which came a week after a bombing claimed by a local ISIS affiliate killed 46 people at a mosque in northern Afghanistan. Taliban spokesman Bilal Karimi confirmed the explosion and said an investigation was underway, without providing further details. Taliban special forces arrived at the mosque to secure the site and an appeal went out to residents to donate blood for the victims. Photographs posted by journalists on social media showed many people apparently dead or seriously wounded on the bloody floor of the mosque. An official in the provincial hospital said their facility received seven dead bodies and 13 wounded, adding that the death toll would likely rise. The official spoke on condition of anonymity because he was not authorized to brief media. The Friday service is typically attended by large crowds of worshippers.