Riyadh: A shooting at a Shiite mosque in eastern Saudi Arabia killed three people and wounded others on Friday during prayers, security officials and a witness said, in the latest violence to strike the region.

The attack struck the Imam Reza Mosque in the neighbourhood of Mehasin, an area popular with Shiite workers of the state-run Saudi Arabian Oil Co., the world's largest oil producing firm. Images on social media showed wounded laying on the mosque's floor. The security officials said the three dead was an initial toll. They spoke on condition of anonymity as a formal announcement had yet to be made.