MENA, Saudi Arabia (Reuters) - More than two million Muslim pilgrims stoned walls symbolizing the devil in a narrow valley outside Mecca in Saudi Arabia Monday at the most dangerous stage of the haj pilgrimage.

Pilgrims began three days of stoning and celebrated the first day of Eid al-Adha, commemorating the willingness of biblical patriarch Abraham to sacrifice his son for God.

“It took a long time since they made us go in one line, but it was easy to do,” said Osama Khashaba, an Egyptian accountant, after throwing stones at the Jamarat Bridge in a ritual that represents rejection of temptation.

The bridge in the valley of Mena just outside Mecca has been the scene of a number of deadly stampedes. The last was in 2006 when 362 people were crushed to death in the worst haj tragedy since 1990.

Saudi authorities have made renovations to ease the flow of pilgrims at the bridge, adding an extra level so that they have four platforms from which to throw stones each day.

Authorities also appealed to pilgrims this year to throw their stones at any time of day rather than only in the afternoon, as Saudi clerics had insisted in the past.

Saudi Arabia has not so far reported any glitches in the haj, a challenging logistical feat that has been marred in previous years by deadly fires, hotel collapses, police clashes with protesters and stampedes caused by overcrowding.

“Let’s make the accidents at the stoning part of history, may it never return,” Saudi television said in one program.

Elaborate crowd control measures, involving security forces and a maze of paths marked by barriers, guided pilgrims to the three spots by the bridge in the Mena valley where they threw stones they had collected overnight at a spot called Muzdalifa.

“This overcrowding is really scary,” said Umm Mohammad, a Syrian pilgrim. “God willing no one will be hurt.”

Pilgrims say performing haj is far more important than worries about accidents. “Praise God, I think this will change me for the better in everything I do after haj,” said Abdullah.

The government has also been tougher this year in preventing Saudis and foreign residents taking part without official haj permits. Saudi media put the pilgrim total at a relatively low 2.4 million people, including a record 1.72 million from abroad -- a sign that the crackdown has worked.

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SHAVED HEADS

Many pilgrims returned to the Grand Mosque in Mecca after the first round of stoning rituals.

They crowded into the mosque in the early hours of the morning and into the day, circling the Kaaba, a cube-shaped structure toward which Muslims around the world turn in prayer.

Afterwards men had their heads shaved, according to the rules of haj. “It will take three minutes a head,” said a man ushering people into a busy barbershop near the mosque.

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The haj retraces the path of Prophet Mohammad 14 centuries ago after he removed pagan idols from Mecca, his birthplace, and years after he started calling people to the new faith, which is now embraced by more than one billion people worldwide.

Sunday, pilgrims spent the day in prayer at Arafat 15 km (10 miles) east of Mecca at the climax of haj, a duty for every able-bodied Muslim once in a lifetime and one of the largest manifestations of religious devotion in the world today.

Although there have been no disasters, Saudi authorities were not able to stop political activities that pilgrims had been asked to avoid.

Iranian television showed Iranian pilgrims Sunday chanting “Death to America” and “Death to Israel.”

Ayatollah Mohammad Mohammadi Reyshahri, head of Iran’s haj mission, said Islam was now resurgent, despite some Muslims’ despair “in the face of Western civilisation’s onslaught.”