More than two million Muslim pilgrims began the symbolic stoning of the devil today, putting to the test new safety measures at a stage of the haj that has seen tragedy in the past.
But the rites were overshadowed by the news that former Iraqi leader Saddam Hussein, a hero to many Sunni Arabs because of his anti-US stance, had been executed at dawn by the US-backed Shia government.
Security fears were already high during this haj season because of sectarian strife between Sunni and Shia Muslims in Iraq and elsewhere in the region.
Many Sunni Arabs were angered by the news but some Iraqi pilgrims were celebrating both Saddam's death and the Eid al-Adha, or Feast of Sacrifice, that began today.
"Congratulations, this is like two Eids! I hope God will not have mercy on him," said Iraqi pilgrim Nadir Abdullah.
The stoning ritual at the Jamarat Bridge, when pilgrims symbolically cast out the devil, begins on Eid al-Adha, the third day of the gruelling 5-day haj which is a duty for all able-bodied Muslims who can afford it.
With such large crowds, Saudi Arabia deploys more than 50,000 security men to try to avoid deadly stampedes, as well as attacks by Islamists opposed to the US-allied Saudi royals.
The authorities are also worried over political protests which security forces have broken up by force in the past.
"The haj rites are not the place for slogans, postures and name-calling," top Saudi cleric Sheikh Abdulaziz Al al-Sheikh warned in a sermon at Mount Arafat on Friday.