Five 10 and 11-year-old boys at an Amsterdam primary school have been caught indecently assaulting girls from their class, according to local broadcaster AT5.

The boys have been threatening, intimidating and sexually molesting the girls at the special needs school for some time, AT5 says. They also bullied other boys into joining in.

The matter came to light in a letter sent by the Knotwilg school to parents and in the possession of the broadcaster.

The boys carried out their bullying on the school playground and were caught red-handed by a teacher outside school hours.

In the letter the school says this was ‘sexual behaviour of a sort that we and you find undesirable’.

The boys have not been suspended from school but are no longer allowed to go on school outings, one parent told AT5.