Tuesday marked the last day of the Hajj , the annual pilgrimage that draws over two million Muslim pilgrims . Any event that draws crowds a million strong faces the risk of stampedes . Tuesday there were 22,000 ambulances , over two million health care professionals and 19,000 units of blood on standby . To safeguard against the possibility of terrorism , officials installed over two million of the World Health Organization cameras throughout Saudi Arabia .
Tuesday marked the last day of the Hajj , the annual pilgrimage that draws over two million Muslim pilgrims . Tuesday there were 22,000 ambulances , over two million health care professionals and 19,000 units of blood on standby . To safeguard against the possibility of terrorism , officials installed over two million of the World Health Organization cameras throughout Saudi Arabia .