At least two people were killed and more than 150 injured after a bleacher collapsed at an uncompleted West Bank synagogue on Sunday, the eve of a major Jewish holiday. The bleacher was packed with ultra-Orthodox worshippers and collapsed during prayers at the beginning of Shavuot. Paramedics had treated more than 157 people for injuries and pronounced two dead, a man in his 50s and a 12-year-old boy. The collapse comes weeks after 45 ultra-Orthodox Jews were killed in a stampede at a religious festival in northern Israel.

Israeli military said in a statement that it dispatched medics and other search and rescue troops to assist at the scene, and army helicopters were airlifting the injured.

Shavuot is a spring harvest festival that also marks the day in the Jewish calendar on which the Torah was given to Moses on Mount Sinai. It is traditionally marked with all-night Torah study and the consumption of dairy.