DUBAI, United Arab Emirates (AP) -- Saudi Arabia's Interior Ministry says four security officers were killed and five others were wounded when a suicide bomber detonated his vest outside one of Islam's holiest sites.

The Monday evening attack took place just as thousands of worshippers were about to hold sunset prayers in the mosque where the Prophet Muhammad is buried in Medina. The mosque is visited by millions of Muslims from around the world annually performing pilgrimage in Mecca.

The ministry statement, carried Monday on the state-run al-Ekhbariya news channel, said the attacker set off the bomb after security officers raised suspicions about him. The attack took place in a parking lot outside the sprawling mosque complex.

Egypt, the United Arab Emirates and Bahrain have condemned blasts in Saudi Arabia, including an explosion outside the Prophet Muhammad's mosque in Medina.

Egypt's Foreign Ministry says the reported attack during the Muslim holy month of Ramadan near one of Islam's most sacred places confirms that terrorism "knows no religion or belief or any meaning of humanity."

A Foreign Ministry official in the UAE was quoted in the state-run WAM news agency as saying the stability of Saudi Arabia "is the main pillar of the stability of the United Arab Emirates and the whole of the Gulf Arab region."

The secretary general of the 57-nation Organization of Islamic Cooperation, which is headquartered in Saudi Arabia, says the attacks are an attempt to destabilize the kingdom. Iyad Madani says the kingdom's security is "the cornerstone of security and stability in the region and the Islamic world."

No group has claimed responsibility for the blasts, which also struck outside a Shiite mosque in the kingdom's east and near the U.S. Consulate in the western city of Jiddah.