A suicide bomber has detonated his explosives at a Shia mosque in eastern Saudi Arabia during Friday prayers, martyring and wounding several people.
One witness described a huge explosion at the Imam Ali mosque in a village in the province of Qatif, where more than 150 people were praying.
A source told that there were at least 30 casualties estimated in the attack.
The Saudi state news agency confirmed an explosion had occurred at a mosque and said more details would be provided later.
Saudi Arabia's Shia population is mostly based in two oasis districts of the Eastern Province - Qatif on the Gulf coast, and al-Ahsa, southwest of the provincial capital al-Khobar.
This is the first time such an incident occurred in this area.
