Police recruitment methods have been put under the spotlight after a BBC undercover documentary exposed racist recruits infiltrating the force.

BBC One’s The Secret Policeman documentary showed disturbing scenes of a racist recruit using a pillowcase as a Ku Klux Klan mask and making racist threats.

BBC reporter Mark Daly (pictured) caught the incident on a hidden camera as he posed as a new recruit to the police service at the Bruche Training College in Warrington, Cheshire.

The documentary could not have come at a worse time for the police force, which is already reeling from the decision by the National Black Police Association (NBPA) not to back the Metropolitan Police’s ethnic minority recruitment scheme.

The NBPA is protesting against Operation Helios, a failed internal investigation by the police into Superintendent Ali Dizaei, one of the Met’s most senior ethnic minority officers.

The association has called for a public inquiry into police recruitment procedures following the BBC’s documentary.

NBPA president-elect Ray Powell told Recruiter that the association was “disgusted” by the extreme racist views of the trainee policemen in the programme.

“This is something that our members have been experiencing for some time,” he said. “There should be a public inquiry into the processes that have allowed racist officers to be recruited and complete the 15-week training course.”

The NBPA is planning to make representations to the Home Office and intends to advise police recruitment centres on how to tackle the problem.