A suicide bomb attack inside a mosque in a local security forces headquarters in Abha city in south-west Saudi Arabia killed 15 people and wounded nine on Thursday, the Saudi state news agency reported, citing an interior ministry spokesman.
Islamic State, also known as ISIS, later claimed reponsbility for the attack in a statement circulating on Twitter.
The group said a suicide bomber had infiltrated a "military camp" for the Special Emergency Force in Asir province. It did not specify that the attack was in a mosque.
The mosque in Abha was part of the local headquarters of a state security unit called the Special Emergency Force, the spokesman was cited as saying.
Of those killed, 10 were members of the force, while three were workers in the compound. They were praying when the bomber struck within their ranks, he said.
In May, two suicide bomb attacks on Shi'ite mosques in Saudi Arabia were claimed by ISIS. The first on a mosque in Qatif in the east of the kingdom killed 21 worshippers, and another four died in a bombing a week later at a mosque in Dammam.
Another bombing claimed by ISIS on a Shi'ite mosque in Kuwait in June killed 27 people.
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