A suicide bomber in the Saudi holy city of Medina detonated explosives Monday at a checkpoint outside one of Islam's holiest sites, the Prophet's Mosque.
Hours later, the Saudi Interior Ministry said four security officers were killed and five others wounded as they moved to prevent the attacker from entering the facility.
The mosque — the second holiest site in Islam — is the burial site of the Prophet Muhammad, who died in 632 AD. It is visited by millions of Muslims from across the globe each year during pilgrimages to Mecca.
Two other explosions were also reported in the kingdom as the holy month of Ramadan draws to a close.
One blast was linked to a suicide bomber at a Shi'ite mosque in the eastern city of Qatif. No casualties were reported.
Hours earlier, the Saudi Interior Ministry said a suicide bomber blew himself up near the U.S. consulate in the western city of Jeddah.
The U.S. embassy reported no casualties or injuries among its staff.
Saudi Arabia declared Wednesday the first day of Eid al-Fitr — the start of three-days of festivals across the Muslim world marking the end of the annual fasting month.