DUBAI: An attack on a Shiite mosque in al-Ahsa in east Saudi Arabia killed three people on Friday, Saudi-owned al-Arabiya television reported.
An activist, citing witnesses, told Reuters earlier that an explosion was followed by gun attack on Imam Rida Mosque in the town of Mahasen in al-Ahsa region in the Eastern Province.
Residents said security forces were exchanging gunfire with five “terrorists”.
Mohammed al-Nimr told The Associated Press the attack struck the mosque during Friday prayers.
Al-Nimr, who is the brother of the executed cleric, Sheikh Nimr al-Nimr. said security forces and ambulances quickly surrounded the mosque.
He said that the attack was a shooting and that worshippers stopped the attacker from detonating a suicide bomb belt.
Saudi state media did not immediately report on the attack.
Shias in Saudi Arabia previously have been targeted in attacks by the Islamic State group in the kingdom.
Earlier this month, Saudi officials also executed a prominent Shia cleric from the region, raising tensions in the area.
Last year, two deadly blasts at Shia mosques in Saudi Arabia had killed scores of worshippers. The Islamic State had claimed the attacks.