The Jewish community has slammed horrific antisemitic bullying at a Sydney private school.

Holocaust survivor Olga Horak said her then-teenage grandson was bullied for being Jewish at Cranbrook in Bellevue Hill 18 years ago.

Now, The Daily Telegraph has revealed more families have come forward with recent cases of antisemitism.

A detailed review has been launched by the school.

NSW Jewish Board of Deputies chief executive Darren Bark told 2GB’s Mark Levy “this is an early warning sign”.

“The fact that children are being bullied simply because they’re Jewish is intolerable.

“If we don’t have respect, understanding and acceptance in our schools, it’s going to lead to history repeating itself again.”