Saudi officials said a stampede Thursday outside the city of Mecca killed at least 310 people and injured 450 others as they took part in the annual Muslim hajj pilgrimage.
The incident happened in Mina where pilgrims throw rocks at pillars representing the devil in the final hajj ritual before beginning the Eid al-Adha festival.
Saudi Arabia's civil defense directorate gave the casualty figures on its Twitter account and posted pictures showing rescue workers attending to people on stretchers, including one who appears to be trying to resuscitate a man.
Multiple deadly stampedes have taken place at the hajj during the past 25 years as huge numbers of people gathered for the five-day event required of all able-bodied Muslims once in their lifetime. This year, some 2 million people are participating.
The worst disaster happened in 1990 when a stampede in a Mina tunnel killed more than 1,400 people. Stampedes in 1994, 2004 and 2006 each killed more than 200 pilgrims.
Earlier this month, a construction crane collapsed at Mecca's Grand Mosque, killing 109 people and injuring about 400 others at Islam's holiest site.