Home Secretary Jacqui Smith has been asked to intervene in a fresh police race row.

It is claimed at least 20 forces blocked an inquiry into discrimination against Muslim officers.

The National Association of Muslim Police said barely half of the 43 forces in England and Wales co-operated in an audit into the treatment of officers from ethnic minorities.

In a letter to Jacqui Smith, Zaheer Ahmad, president of the association, also claimed information from the forces that did respond suggested routine racial harassment.

Referring to ten years since the inquiry into the murder of Stephen Lawrence found the Metropolitan Police to be 'institutionally racist', an association spokesman said its audit revealed: "we still do not have the level of diversity that the public rightly expects."

He added progress on diversity has been "painfully slow".

The revelations come just days after it emerged Tarique Ghaffur, Britain's most senior Muslim officer, was considering suing the Metropolitan police for discrimination.

From the data provided to the association, it was revealed 95 per cent of black and minority ethic officers were in the most junior rank.

Figures also revealed Muslim officers were almost "entirely absent" from specialist operations such as counter-terrorism, a move Mr Ahmad believed was hampering the fight against terrorism.

In the questionnaire, the association asked forces about the promotional prospects, rank and number of Muslim and black officers employed.

Initially just 11 of the 43 forces replied and 23 co-operated when the deadline was extended.

From the replies it received, just 0.3 per cent of police officers were found to be Muslim, compared with three per cent of the British population.

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