A white actor “blacked-up” to play an African government official in a role-play exercise staged by the elite squad leading the fight against organised crime, The Times has learnt.

The incident, which has led to accusations of crass racism, occurred in a recruitment process for candidates applying to be overseas liaison officers for the Serious Organised Crime Agency (Soca).

A high-level internal investigation into the racism claims is under way. The allegation involving Soca - which boasts on its website that it “fully embraces the principles of diversity” - is the latest in a series of race rows threatening to engulf police and law enforcement agencies.

Sir Ian Blair, the Metropolitan Police Commissioner, is facing accusations of racism from two high-ranking Asian officers, Tarique Ghaffur and Shabir Hussain, and the Association of Muslim Police has accused 20 police forces of refusing to cooperate with an audit of discrimination in the service.

The incident at Soca occurred last month during recruitment for officers who would be stationed overseas. The agency, described as Britain’s answer to the FBI when it was set up in 2006, has 140 officers based abroad. The largest deployment is in Afghanistan where they work to stem the heroin trade. Soca agents are also active in West Africa, which is a conduit for cocaine being smuggled from Colombia to Europe.

During the recruitment process, it is alleged that Soca enlisted the services of an actor who had previously been used in training exercises.

The man, who was white, is said to have dressed in traditional African clothing and wore black face make-up to play the part of a representative from a difficult regime. The situation shocked several people taking part and provoked at least one official complaint.

One Soca source said: “The most infuriating thing about this is that there are a lot of people in the organisation who cannot see what they have done wrong.

“This is the department responsible for international relations yet they go and do something as crass and low as this and cannot understand what the fuss is about.”

Another source said: “It really beggars belief that someone could do something quite as stupid as this.”

Bill Hughes, the director-general of Soca, was said to be furious when he heard of the exercise and ordered an immediate inquiry. It is being carried out by Andy Baker, one of Soca’s deputy directors and a former head of murder inquiries at Scotland Yard.

A spokesman for the agency refused to discuss specific details of the allegations but confirmed that an internal review was in progress.

The spokesman said: “There has been a complaint about part of a recruitment process and there is an investigation ongoing. It is important for the organisation to ascertain what has happened and what the basis of the complaint is.”

Jeremy Gautrey of the PCS union, which represents Soca staff, confirmed that he had been consulted over the incident. He said: “If the accusation is true it is extremely concerning. What this identifies is a clear need for equality and diversity training within the organisation to make sure this sort of thing never takes place again.

“Soca has, however, acted quickly to launch an inquiry and is taking the issue seriously at the highest levels.”

Soca has been affected by repeated reports of low morale among staff who complain that the agency is undertaking too little investigative work and is burdened by a top-heavy management structure.

In May sources within the agency told The Times that it had had to abandon its hitlist of 130 organised crime barons after realising that the intelligence behind it was out of date and flawed.

It is now working with police forces to build up a more reliable picture of criminal networks encompassing some 15,000 suspects.

Soca’s leadership has reacted angrily to the criticisms and said they stemmed largely from staff who were disenchanted with its new approach to investigation which focused on gathering intelligence about organised crime groups.

Changing attitudes

1967 Campaign against Racial Discrimination petitions BBC to take Black & White Minstrel Show off air. It stays on screen until 1978

1985 Royal Shakespeare Company begins to cast only black actors in the part of Othello - first played by Willard White

2000 Rotherham council bans “blacking up” in all productions on premises it owns

2005 The Royal Opera ends “blacking up”

2007 Residents of Padstow, Cornwall, still “black up” for a festival known as “Darkie Day”

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