MEDINA : Four security officers have been killed and five others injured in a suicide attack outside the Prophet's Mosque in Saudi Arabia's Medina, Islam's second holiest city, the Saudi interior ministry said.
Photos on social media show smoke billowing from a fire outside the mosque where Prophet Muhammad is buried.
"Four security guards were martyred and five others wounded as a result of their opposition to the suicide attacker who detonated the explosives near them as he was on his way to the mosque," the ministry said on Twitter.
The blast occurred just before the Maghreb (sunset) prayers on Monday when people were breaking their fast inside the mosque, visited by pilgrims from around the world for the final days of the fasting month of Ramadan.
Qari Ziyaad Patel, 36, from South Africa, was at the mosque when he heard a blast just as the call to prayers was ending.
Many at first thought it was the sound of traditional, celebratory cannon fire, but then he felt the ground shake.
"The vibrations were very strong," he told the AP news agency. "It sounded like a building imploded."
Saudi Arabia's state-run news channel, Al-Ekhbariya, aired live video of thousands of