The death toll following a crush at the annual Hajj pilgrimage in Saudi Arabia is now 769 and the number of injured has risen to 934.
Witnesses claimed police had closed entrances and exits to the pilgrims' camp, making the disaster inevitable, while Iran's Supreme Leader accused authorities of "mismanagement".
King Salman has ordered an immediate review into safety procedures.
Iran's supreme leader has demanded that Saudi Arabia apologise to families of the victims of the Hajj stampede which killed 769 worshippers performing the annual pilgrimage.
Ayatollah Ali Khamenei said : "This issue will not be forgotten and the nations will pursue it seriously.
"Instead of accusing this and that, the Saudis should accept the responsibility and apologize to the Muslims and the victims' families.
"The Islamic World has a lot of questions."
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