Mr Lowther said he had no option

Colin Lowther, 48, head of Southfield Primary in Southfield Road, Ealing, west London, has made the decision following a fight in the playground which he says has left pupils severely traumatised.

A parent and a parent governor were injured during the incident last week.

Ealing Council says pupils should not be held responsible for the actions of their parents but Mr Lowther says he is responsible for the safety of the school and has no option but to exclude them.

The head says the fight followed several months of aggressions from two traveller families who have a total of six children attending the school.

It is alleged the fight involving one of the children's mothers, two of their teenage siblings and a Somali mother, started due to an argument over a chocolate biscuit.

"Completely traumatised"

A parent governor at the school claimed when she intervened to help the Somali mother she received cuts and bruises and had hair pulled from her head.

The Somali mother is said to have suffered a broken finger.

Mr Lowther told BBC London: "Some of the tiniest children didn't sleep that night, some had to sleep with their parents, we've had some children bed wetting, we've had children just completely traumatised."

One parent who was collecting his child from the school when the incident took place told BBC London: "I had to concentrate on leaving with my daughter as quickly as possible so that she didn't witness any further violence.

"Fortunately she doesn't appear to have been seriously affected by the incident, although I understand from speaking to other parents their children have."

A council statement said action was being taken to ban "those causing violence" from the school premises but excluding pupils would not "satisfactorily" resolve the problem.

Mr Lowther has written to the children's parents excluding them but the move is not legally binding and the pupils could return on Thursday.