Muslim pilgrims pray around the Kaaba, center, inside the Grand Mosque, Islam's holiest shrine, in Mecca, Saudi Arabia

More than two million Muslims from around the world have gathered at Mount Arafat in Saudi Arabia to offer prayers during the annual pilgrimage, or hajj.

The pilgrims heard the kingdom's grand mufti, Sheikh Abdul Aziz al-Sheikh, speak about the challenges facing Muslims.

After Monday's prayers, the pilgrims trekked back to the Mina Valley before Tuesday's symbolic stoning of the devil, throwing pebbles at three pillars.

The stoning ritual has led to hundreds of fatalities in recent years because so many people try at the same time to get close to the pillars, often causing people to slip, fall and be trampled. 

This year, Saudi officials reorganized access to the area and deployed 60,000 security personnel to avoid such accidents.