MECCA, Saudi Arabia (AP) — At least 220 people were killed and hundreds injured in a stampede Thursday at the annual hajj pilgrimage, Saudi authorities said.

The crush happened in Mina, a large valley about five kilometers (three miles) from the holy city of Mecca. Mina houses more than 160,000 tents where pilgrims spend the night during the pilgrimage.

The Saudi civil defense directorate said at least 450 other pilgrims were injured in the stampede.

Photos released by the directorate on its official Twitter account showed rescue workers in orange and yellow vests helping the wounded onto stretchers and loading them onto ambulances near some of the white tents.

Some 2 million people are taking part in this year's hajj pilgrimage, which began Tuesday.

The stampede was the deadliest disaster at the hajj since 2006, when more than 360 pilgrims were killed in a stampede in the same area.

Mina is where pilgrims carry out a symbolic stoning of the devil by throwing pebbles against three stone walls.

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 killed at least 111 people and injured more than 390.