The statement said “the soldiers of the Caliphate” were behind the attack by a suicide bomber “who detonated an explosives belt” in the mosque in the Shiite-majority city of Qatif.
It identified the bomber as Abu Amer al-Najdi, and published a picture of him.
He struck during the main weekly prayers in Eastern Province, where assailants linked to the Sunni extremist IS killed seven members of the minority Shiite community in November.
Several people were killed and wounded in the blast at the Ali Ibn Abi Taleb mosque, but an exact toll is not yet known.
The IS statement pledged “dark days ahead” for Shiites until militants “chase them from the Arabian Peninsula”. – AFP