Extraordinary photos show millions of joyful Muslims descending on Mecca's Grand Mosque for start of Islam's annual haj pilgrimage
- Saudi authorities warn they will stop any disruptive protests at annual pilgrimage in Mecca over the conflict in Syria
- Grand Mosque teeming with joyful pilgrims at dawn yesterday, wearing simple white folds of cloth prescribed for haj
- Authorities say there have so far been 1.7million arrivals from abroad and about 200,000 from inside Saudi Arabia
- Last year nearly 3million pilgrims performed the haj, with roughly a third from inside the conservative kingdom
