The death toll in a mosque blast in southern Iran has risen to 12, and 202 people have been wounded, Iranian media reported on Sunday.

The explosion occurred on Saturday evening in a crowded mosque in the city of Shiraz, the capital of the southern province of Fars, the media said.

Local police said the possibility of sabotage had not yet been proved, adding that the explosion might have been caused by negligence involving explosives left behind from an earlier exhibition held near the mosque.