Hundreds of thousands of Muslim pilgrims massed in a valley near the Saudi holy city of Mina on Monday for the stoning of Satan, the last and most dangerous rite of the annual haj.
Hundreds of people have been trampled to death in stampedes which have blighted several previous pilgrimages to Islam's holiest sites when the faithful rush to hurl stones at pillars symbolising the devil.
So far this year, no major incidents have been reported, although a record number of pilgrims from abroad travelled to the holy sites, with a total of more than two million worshippers.
A large security force was monitoring the pilgrims as they gathered for the stoning after slaughtering sheep in a ritual for the Feast of the Sacrifice (Eid al-Adha) to recall Abraham's willingness to sacrifice his son on God's order.
The authorities have built bridges at three different levels on the stoning site in a bid to avoid the trampling that caused the deaths of 364 people in 2006, 251 in 2004 and 1,426 in 1990.
The interior ministry has assembled 100,000 stewards to ensure safety during the haj, one of the five pillars of Islam which the Koran says Muslims must carry out at least once in their lives if they are well enough and can afford it.
The ministry said on Saturday that almost 1.73 million pilgrims had entered the kingdom from abroad, the highest number ever, joining hundreds of thousands of Saudi citizens and other residents participating this year.