Parents at Mill Hill Synagogue have been asked to keep a closer eye on their children at Yom Kippur after a classroom was damaged during Rosh Hashanah.

Paul Charney, chairman of the United Synagogue congregation, wrote to members that he was “deeply upset by the disregard that a minority of the children of our community demonstrated” during the New Year services.

The behaviour of some children on the synagogue site was “unacceptable,” he said, “showing little respect to the service leaders, volunteers and paid staff, whose only purpose on the day was to help.”

A classroom had been “vandalised” by some children, leaving the synagogue to bear the cost, he said.

It was the responsibility of parents to ensure children were “on their best behaviour at all times”.

Mr Charney told the JC there had been “limited damage by a small number of over-enthusiastic kids”.

He added: “We have a vibrant youth community and we want them all to attend but they need to be mindful of their behaviour.”

Rabbi Yitzchak Schochet, Mill Hill’s rabbi, said: “Mill Hill boasts the largest proportion of children than any other individual community in the UK - and arguably, by extension, all of Europe.

“It is inevitable that sometimes something can go wrong. It is the first time and so we would naturally look to address it immediately in anticipation that all will be good. We look forward to continue catering to our ever thriving and child-friendly community.”