Sunni Muslims Throw Shoe at Iranian President
Ahmadinejad is a Shiite Muslim and the four men were Sunni.
The mosque Ahmadinejad visited--the Al-Hussein Mosque--is "revered by Shiites" but is "widely disliked by Sunni Muslims."
Sunni Muslims had been protesting Ahmadinejad's trip from the moment it was planned, and had asked Egypt's government to prevent the Iranian President from visiting any religious sites "significant to Shiite Muslims" during his visit.
Reports indicate that Ahmadinejad was never in danger.