Last November Paul Boateng ordered improvements at Brixton

Sexual discrimination was also reported to be common, including one case where an officer physically assaulted a junior governor after refusing to carry out her instructions.

The investigators report, which has now been passed to the Commission for Racial Equality (CRE) by director general of the Prison Service, Martin Narey, also found that systems to eradicate or investigate discrimination were not in place at the prison.

"At the highest levels in the organisation, it was plain that racial issues were not given appropriate priority," the report concludes.

Mr Narey sent the team of investigators into Brixton in May this year.

Victimisation

He said he had been dissatisfied with the prison's response to instances of harassment.

Brixton may be a bad example, but it is not alone

Martin Narey, Prison Service

Records kept by prison staff showed six recorded complaints made on racial grounds in the past two years.

These included the case of Claude Johnson, a black prison officer who returned to work at Brixton after winning damages for race discrimination only to suffer further victimisation.

Another widely publicised case was that of Dee Douglas, who was insulted by her white colleague, junior governor Ian Davis, who joked about her being able to understand the bongo drums.

As punishment, he was sent on a one-day race relations course. Many staff told the race relations investigation team they felt Mr Davis should have been sacked.

Disciplinary action

The main body of the report has not been published because of several allegations made against named prison officers.

They are the subject of other internal investigation and could face disciplinary charges.

Over 80 recommendations are included in the report. Some have already been implemented, said Mr Narey.

He said: "I have already acknowledged that the service is not only institutionally racist, but that pockets of blatant racism still exist.

"Brixton may be a bad example, but it is not alone.

"I acknowledge the failings of Brixton but I am determined that, working closely with the CRE, we can eradicate all racism, both at institutional and individual levels and ensure that the equal opportunities standards of the Prison Service are met."