At least 717 pilgrims were killed on Thursday in a stampede outside the Muslim holy city of Mecca, Saudi authorities said, the worst disaster to strike the annual hajj pilgrimage in 25 years.

According to Reuters, at least 805 others were injured in the crush at Mina, a few kilometers east of Mecca, caused by two large groups of pilgrims arriving together at a crossroads on their way to performing the "stoning the devil" ritual at Jamarat, Saudi civil defense said.

Thursday's disaster was the worst to befall the pilgrimage since July 1990, when 1,426 pilgrims were crushed to death in a tunnel near Mecca. Both stampedes occurred on Eid al-Adha (Feast of the Sacrifice), Islam's most important feast and the day of the stoning ritual.

Photographs published on the Twitter feed of the Saudi civil defense on Thursday showed pilgrims lying on stretchers while emergency workers in high-visibility jackets lifted them into an ambulance.

The haj, the world's largest annual gathering of people, has been the scene of numerous deadly stampedes, fires and riots in the past, but their frequency was greatly reduced in recent years as the government spent billions of dollars upgrading and expanding haj infrastructure and crowd control technology.

Safety during haj is a politically sensitive issue for the kingdom's ruling Al Saud dynasty, which presents itself internationally as the guardian of orthodox Islam and custodian of its holiest places in Mecca and Medina.

Meanwhile, the Foreign Affairs Ministry said no Sri Lankan had been affected in the Mecca stampede according to the reports received so far by the Sri Lankan mission in Saudi Arabia.

“Our mission is keeping in touch with the local authorities there, to find if any Sri Lankan had been affected. However, so far the reports say no one had been affected,” a ministry official said.