Two million Muslims have gathered in Mina in Saudi Arabia for the annual haj pilgrimage, which began on Tuesday.
On Wednesday, which is marked as the Day of Arafat, Muslims will gather at Mount Arafat, where Prophet Mohammed is believed to have given his last sermon.
The Day of Arafat is observed as a day before Eid al Adha, which will be celebrated on Thursday in Saudi Arabia and many other countries.
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Performing the haj is one of the five pillars of Islam and every Muslim is expected to go on the pilgrimage at least once.
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This year, the haj pilgrimage has been marred by several accidents and mishaps, especially the deadly crane crash at the Grand Mosque on 11 September that killed more than 100 pilgrims. Two incidents of fire breaking out at hotels in Mecca where pilgrims were staying were also reported.
You can watch the live streaming of the Haj 2015 pilgrimage in the videos below: