Suicide bombings have struck the sacred city of Medina just outside the Prophet Muhammad's burial site.
Medina
The suicide bombing hit Saudi Arabia's city of Medina, close to the Prophet's Mosque, one of Islam's holiest sites in Mecca.
This was revealed by al-Arabiya TV and the Okaz newspaper.
There are no details of casualties and no official comment.
The mosque is the burial place of the Prophet Muhammad and Medina the second-holiest city in Islam after Mecca.
Earlier, at least one explosion rocked the eastern city of Qatif.
Qatif is home to many minority Shia Muslims and the blast appeared to target a Shia mosque. No casualties have been reported so far.
It is not clear who is behind any of the attacks.
The attacks come with the holy month of Ramadan drawing to a close and ahead of the Eid al-Fitr holiday.