The rumour of a fight turned out to be true.

A large group of black pupils from my school met up with a large group of Asian pupils from a neighbouring school in order to sort out a difficulty with violence.

The time for discussion was over. The confrontation was ugly. Now it was aggressive words and even more aggressive action. It took some time for teachers and police officers to bring the situation under control.

In assembly the following week I told our 1,100 pupils this sort of behaviour was unacceptable and it was an example of racism. Later in the morning, a black girl said to a teacher "It wasn't racism, we just don't like Asians."

Four years on, I still find her comment disturbing.

Parents, teachers and community leaders all do their best to teach young people the difference between right and wrong and the unacceptability of violence - but to what effect?

The mind of at least one 15-year-old appears to be caught in a time-warp. She seriously believes violence against another ethnic group is only racism if it's done by white people.

I was reminded of her comment when I saw a recent documentary on Channel 4. It was called, uncompromisingly "Who are you calling a N****r?" and dealt with street violence between people of different ethnic minority groups.

The film reported that the problem is on the increase and highlighted violence in London and the Midlands involving young people from Black Caribbean, Pakistani and Somali communities.

Apparently, there are similar difficulties in other parts of the country.

The violence may be related to historical, political or religious differences or simply be the flexing of muscles to decide who rules the local streets.

But whatever the reason it is racism. Members of one ethnic group who deliberately discriminate against another group are racist, whatever their ethnic background. The motives may be dressed up in fancy words and high-sounding excuses but the ugly word 'racism' remains.

In the UK we have rightly been tough on racial discrimination and abuse and during the past two decades our commitment to stamp out racism has been high-profile and determined. In the early days, most offenders were members of the white population while most victims were members of various ethnic minority communities. But the pattern is changing and racism has taken hold among groups of people it was designed to protect and support.

Perhaps our efforts have got sidetracked. There are certainly occasions when official bodies and professional anti-racists seem happier to criticise organisations for shortcomings than to celebrate their successes.

This might suggest that racism in the UK really does refer only to what white British people and their organisations do to everyone else.

It may be a travesty of the motives of people who are trying to raise our awareness of the issues but this perception appears to be growing in some areas where there is racism between ethnic-minority groups.

It would be helpful if anyone believed racism carried out by members of ethnic minority groups on the streets was a serious issue. However, with the exception of Channel 4, I have yet to find a national public body that has categorically stated that this sort of inter-ethnic conflict is an example of racism and therefore morally wrong and illegal.

When I contacted the Commission for Racial Equality last week, they were unable to refer me to any reports on the matter, far less any judgements. They have plenty of reports dealing with inequalities in the application of justice, health, housing and education services to people in ethnic-minority groups and these reports make adverse judgements about institutional racism. But, apparently, there are no reports on the inequalities of expectations regarding compliance with the laws on racism.

So what? What has a problem, concentrated in London and the Midlands, got to do with Brighton and Hove? Here, the relations between people are largely harmonious, irrespective of ethnic origin.

But those good relations took time to build and are far too easy to destroy. Just a few short years ago, many other regions across Britain had the sort of positive relationships that we, in Brighton, take for granted. Now it appears those qualities of trust and understanding are disappearing and being replaced by suspicion, violence, lawlessness and fear.

Perhaps people were so busy dealing with the letter of the law that they lost contact with its spirit.

Perhaps people were too preoccupied jumping through the bureaucratic hoops of race relations legislation to see disaffected young people from ethnic minorities initiating racism on the streets.

Perhaps people of goodwill, especially if they were white, found that if they disagreed with the current version of political correctness on a racial issue, it was better to be silent and thought a racist than open your mouth and be accused of being one.

I don't know. But nobody else does either because there does not seem to be any report into why things have gone so badly wrong in some parts of the country.

We need to know. We must learn from the difficulties elsewhere so we can take positive action to ensure they do not happen here.

The whole city benefits from our broad ethnic mix. We need to ensure every person, irrespective of ethnic background, continues to live and thrive here. The alternative is unthinkable.

-Stuart Newton, Peacehaven, Headmaster 1980-2001, Selsdon High School, Croydon