At least 769 people were killed and 934 were injured in a stampede Thursday on the outskirts of Mecca, the deadliest such tragedy to strike the annual hajj pilgrimage in nearly a decade. A Turkish pilgrim was later confirmed dead in the incident, while 12 others still remain missing. It was the second major disaster during this year's hajj season, raising questions about the adequacy of measures put in place by Saudi authorities to ensure the safety of the roughly 2 million Muslims taking part. A crane collapse in Mecca nearly two weeks earlier left more than 100 people dead.Thursday's crush happened in Mina, a large valley about five kilometers (three miles) from the holy city of Mecca that has been the site of hajj stampedes in years past. Mina is where pilgrims carry out a symbolic stoning of the devil by throwing pebbles against three stone columns. It also houses more than 160,000 tents where pilgrims spend the night during the pilgrimage.The stampede occurred in a morning surge of pilgrims at the intersection of streets 204 and 223 as the faithful were making their way toward a large structure overlooking the columns, according to the Saudi civil defense directorate. The multi-story structure, known as Jamarat Bridge, is designed to ease the pressure of the crowds and prevent pilgrims from being trampled.Four Turkish pilgrims have reportedly died in the stampede. Mehmet Görmez, Head of Turkey's Presidency of Religious Affairs (Diyanet), stated that 14 Turkish pilgrims who arrived in Mecca with two private travel agencies remain missing. Görmez said that Diyanet had earlier instructed Turkish pilgrims not be present at the stampede area during the day through guide books and group leaders, and all pilgrims who arrived Mecca with Diyanet performed stone throwing at night. "There was serious negligence by authorities in directing the crowd" Görmez said, however, he also noted that Saudi authorities make important efforts to provide safe conditions during Hajj.The civil defense directorate, which provided the death toll, said at least 631 other pilgrims were injured in the stampede on Street 204 in Mina. Ambulance sirens blared as rescue crews rushed the injured to nearby hospitals. More than 220 rescue vehicles and some 4,000 members of the emergency services were deployed soon after the stampede to try to ease the congestion and provide alternative exit routes, according to the directorate.Amateur video shared on social media showed a horrific scene, with scores of bodies the men dressed in the simple terry cloth garments worn during hajj lying amid crushed wheelchairs and water bottles along a sunbaked street. Survivors assessed the scene from the top of roadside stalls near white tents as rescue workers in orange and yellow vests combed the area. Photos released by the directorate on its official Twitter account showed rescue workers helping the wounded onto stretchers and loading them onto ambulances near some of the tents.Some 2 million people are taking part in this year's hajj pilgrimage, which is an obligation of every able-bodied Muslim. The pilgrimage began in earnest Tuesday. Saudi authorities take extensive precautions to ensure the security of the hajj and the safety of pilgrims. There are about 100,000 security forces deployed this year to oversee crowd management and ensure pilgrims' safety during the five-day pilgrimage.At Mina specifically, authorities have put measures in place over the years to try to alleviate the pressure posed by masses of pilgrims converging on the site of the stoning ritual. Officials use surveillance cameras and other equipment to limit the number of people converging on the site, and the Jamarat Bridge has multiple exits to facilitate the flow of people.But tragedies are not uncommon.This year's stampede was the deadliest disaster at the hajj since 2006, when more than 360 pilgrims were killed in a stampede near the site of Thursday's incident. Another stampede at Mina in 2004 left 244 pilgrims dead and hundreds injured.Thursday's stampede happened less than two weeks after a giant construction crane came crashing down on the Grand Mosque in Mecca, the focal point of the hajj. That accident, on Sept. 11, killed at least 111 people and injured more than 390.Authorities blamed the crane collapse on high winds during an unusually powerful storm, and faulted the construction giant Saudi Binladin Group, which oversees construction at the mosque, for not following operating procedures.