Casualties feared as explosion goes off inside mosque in southern city during Friday prayers.

An explosion has gone off inside a Shia mosque in Afghanistan’s southern city of Kandahar, according to security sources.

The explosion on Friday afternoon  took place in the Bibi Fatima mosque, the largest mosque for Shia worshippers in the city.

Hospital sources told Al Jazeera they were inundated with patients, and that based on the number of increasing intakes, they feared a high casualty toll.

There was no immediate claim of responsibility.

The incident took place a week after dozens of people were killed and more than 100 others were wounded  when a mosque in the northern province of Kunduz was targeted in an ISIL-K claimed bombing.

The Taliban-led government promised a quick response and to hold the perpetrators for the Kunduz attack responsible.

More to follow.