A barmitzvah celebration caused an unexpected casualty last weekend when sweets thrown by the congregation in honour of the barmitzvah boy hit the rabbi in the face and caused a nosebleed.

Wembley Synagogue's Rabbi Simon Harris got caught in the cross-fire when, at the end of the service, the congregation aimed their sweets towards the bimah. That is when blood was spilled.

"It definitely came from the ladies' gallery," said Rabbi Harris afterwards. "I thought it was very funny and it was a lovely barmitzvah. There will be no suing and no recriminations. It hasn't spoiled my beautiful Jewish nose."

The rabbi was forgiving. "What happened shouldn't stop people throwing sweets," he said. "If it made them giggle, even better. Anything that makes people happy should be encouraged."

Sweet-throwing in shul has become a phenomenon in recent years. Believed to be a Sephardi tradition, it denotes wishes of a sweet life for the barmitzvah boy, or for a new bride and groom in the case of an aufruf (call-up).

The London Charedi Rabbi Abraham Pinter said: "Sometimes people throw big, whole packets, but the children are very able and do their best to intercept. We do need to look at this sensibly and safely, rather than banning it."

But Rabbi Brian Fox of Manchester's Menorah Synagogue described it as a "stupid custom that should be banned". He said: "Teenagers use the sweets as missiles - and they aim for the rabbi. I duck behind my desk. Someone will have their eye out one day. I once had a barmitzvah boy who threw the sweets back, and it started a throwing match."

But the sweets may be a step too far. According to Hilary Pomeroy, lecturer in Sephardi culture at University College London, Sephardim would more customarily throw rose petals - unlikely to hurt anyone.