Saudi Arabia's highest religious body has denounced the three suicide attacks in the kingdom on Monday, including one near Islam's second holiest site.
The Senior Council of Ulema said the bombers had "violated everything that is sacred".
Four guards were killed near the Prophet's Mosque in Medina, while only the bombers died in Jeddah and Qatif.
No group has yet said it was behind the attacks, but suspicion has fallen on so-called Islamic State (IS).
The Sunni Muslim jihadist group has called for the overthrow of the Saudi monarchy and its supporters have previously carried out bombings in the Gulf state, targeting the Shia minority community and security forces.
IS has also claimed, or been blamed for, a series of deadly attacks in the predominantly Muslim countries of Turkey, Bangladesh and Iraq during the holy month of Ramadan.
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In Monday's first bombing, two security officers were wounded when a man detonated an explosive vest he was wearing near the US consulate in the coastal city of Jeddah shortly after midnight.