Another bomber blew himself up earlier in the day near the US consulate in the Red Sea city of Jeddah, injuring two security officers. (AFP photo)
A suicide blast struck Monday in Saudi Arabia outside one of Islam's holiest sites, the Prophet's Mosque in Medina, a Saudi-owned television channel reported.
Al-Arabiya news channel showed images of fire raging in a parking lot with at least one body nearby.
The explosion occurred in a security forces parking area, Al-Arabiya reported.
Two other bombers blew themselves up earlier Monday on opposite sides of the kingdom, which has previously been targeted by the Islamic State group of Sunni extremists.
In Shiite-dominated Qatif, on the Gulf coast, residents said a suicide bomber blew himself up outside a mosque frequented by the minority community.
Another suicide bomber detonated his explosives earlier near the US consulate in the Red Sea city of Jeddah, injuring two security officers.