Black and Asian Probation Service staff still feel isolated and discriminated against by colleagues despite efforts to combat racism, a new report has found.

The chief inspector of probation revealed on Tuesday that the number of incidences of racism against staff by offenders has fallen but that reported cases of "isolation in the workplace" had gone up.

Although the number of officers reporting cases of racism from fellow staff also went down, it did so by less than the rate of reduction of racism from offenders, according to Professor Rod Morgan's report.

Probation officers experiencing racism from offenders fell from 52 per cent to 32 per cent in the past three years while the proportion experiencing racism from colleagues, staff from other agencies or members of the public went down from 57 per cent to 50 per cent.

Feelings of "isolation in the workplace" among ethnic minority staff increased from 24 per cent to 26, despite a big push on the issue following a heavily critical study in 2001.

Professor Morgan, who on Tuesday was also appointed as the new chairman of the Youth Justice Board for England and Wales, said overall progress had been good with 11 out of 19 recommendations having been met.

"This is a positive report overall," he said. "The National Probation Service has made significant strides and greatly improved its performance."

But he questioned internal complaints procedures and called for a more robust approach from managers in handling alleged racism cases.

"Many staff said they were worried about pursuing a complaint as it would invite more victimisation or they felt they would not be believed," he said.

"Although it was apparent that some managers were regarded as effective when dealing with complaints of racism, others were not trusted or suspected of complacency and collusion."

In response, Probation Service director general Eithne Wallis welcomed the report but said "there is no room for complacency".

"In the Probation Service, as in all parts of the criminal justice system, we depend on the confidence of the communities that we serve," she said.

"The Probation Service has made progress on a number of fronts, particularly in recruiting and retaining a workforce that at all levels reflects the diversity of the population, and seeing these staff members flourish and rise through the ranks.

"We will take on the recommendations of the inspectorate's report and continue to strive for improvement in equality of treatment of offenders and opportunity for staff, not least because diverse organisations are more effective and healthy places to work. Diversity is an asset, not an issue."

Welcoming Professor Morgan's appointed as the head of the Youth Justice Board, home secretary David Blunkett said the former academic would bring "vision and energy" to the role.