Dozens of people were injured, 20 of them critically, after a grandstand collapsed at a Jewish pilgrimage site in the north of Israel, local rescue services said early Friday.

Emergency services and ambulances “are treating dozens of injured” including “20 patients in a critical state”, Zaki Heller, spokesman for Magen David Adom, the Israeli emergency service, said in a statement.

Tens of thousands of Jews were participating in the annual pilgrimage on Thursday, for the feast of Lag BaOmer.

But after midnight, a grandstand collapsed, triggering scenes of panic. Emergency services deployed helicopters to evacuate the injured.

Israeli media published an image of a row of bodies covered in plastic bags on the ground.

The pilgrimage for the feast of Lag BaOmer is staged in Meron around the reputed tomb of Rabbi Shimon Bar Yochai, a second-century Talmudic sage.

Authorities had authorised 10,000 people to gather at the site of the tomb but organisers said more than 650 buses had been chartered from across the country, bringing 30,000 pilgrims to Meron.

Around 5,000 police had been deployed to secure the event, the country’s largest public gathering during the coronavirus pandemic.