Two people are dead and more than 100 injured after a grandstand in a West Bank synagogue under construction collapsed at the start of a Jewish holiday.

The tiers were packed with hundreds of ultra-Orthodox worshippers when they fell during prayers at ceremony to mark the beginning of Shauvot today.

A 12-year-old boy and a man in his 50s have been pronounced dead and paramedics are treating at least 157 people for injuries, according to Israeli authorities.

The disaster comes just two weeks after 45 pilgrims were crushed to death in a stampede at the burial site of a Jewish sage in northern Israel.

Amateur footage showed the seating collapse and people falling on top of each other.

Rescue workers including military helicopters and ambulance are on the scene in Givat Zeev, just outside Jerusalem, ferrying the injured to hospital.

Rescue workers transport an injured boy to an ambulance outside a synagogue
Rescue workers transport an injured boy to an ambulance outside the synagogue
Rescue workers transport injured man to an ambulance outside a synagogue where a grandstand collapsed during a religious celebration in Givat Zeev
Wounded worshippers were taken to hospital in ambulances

The Israeli military said in a statement that it dispatched medics and other search and rescue troops to assist at the scene.

Israeli authorities have pointed the finger at one another in the aftermath but all said that the ceremony took place in a partially constructed synagogue.

The local mayor, senior fire brigade and police officers said it went ahead despite the lack of a permit and official warnings that the building zone was unsafe.

Members of the Israeli security forces evacuate an injured an ultra-Orthodox Jewish man after the collapse
Members of the Israeli security forces evacuate an injured an ultra-Orthodox Jewish man after the collapse
Ultra-Orthodix Jewish men evacuate an injured man after the collapse of grandstand seating at a synagogue in the Israeli settlement of Givat Zeev in the occupied West Bank outside Jerusalem, on May 16, 2021,
More than a hundred have been injured, according to Israeli authorities

The mayor said the building was unfinished and dangerous, and that the police had ignored previous calls to take action.

Jerusalem police chief Doron Turgeman said the incident was caused by negligence and that there would likely be arrests.

Deddi Simhi, head of the Israel Fire and Rescue service, told Israel’s Channel 12: “It doesn’t even have a permit for occupancy, and therefore let alone holding events in it.”

A view inside a synagogue where a grandstand collapsed during a religious celebration in Givat Zeev, in the occupied West Bank, May 16, 2021. REUTERS/Ronen Zvulun
A view inside the building where the stand collapsed
A view inside a synagogue where a grandstand collapsed during a religious celebration in Givat Zeev, in the occupied West Bank, May 16, 2021. REUTERS/Ronen Zvulun
A tiered structure fell with hundreds of worshippers standing on it

Initial reports from Israel's Magen David Adom ambulance service said medics "provided care to about 60 injured, including about 10 in critical and severe condition".

Later it was confirmed at least 100 attendees were wounded.

A police spokesman said 650 worshippers were at the Givat worship site for the start of the Jewish holiday of Shavuot.