The Metropolitan Police Commissioner, Bernard Hogan-Howe, today vowed to stamp racism out of the force.
He told London Tonight that he would be an 'implacable enemy' to racists - and that he would root them out of the force. But he defended the 'vast majority' of his staff as professional and unprejudiced.
The Commissioner admitted that training in one of the most controversial police tactics - stop and search - could be improved, and that the force would focus on that in the coming year.
During his visit to LBC 97.3 radio, Mr Hogan-Howe was confronted by the brother of black bus driver Kester David, whose suspicious death in 2010 is to be reinvestigated by the force.
In a recording played to Mr Hogan-Howe, Roger David said:
Mr Hogan-Howe told radio host Nick Ferrari:
The force announced it would reinvestigate the death of Mr David, 53, almost two years after his charred remains were found under a railway arch.
Relatives campaigned for an independent inquiry after officers, who originally ruled out foul play, were accused of a catalogue of errors.
Ten other complaints of alleged racism - relating to 18 officers and one member of police staff - were referred to the police watchdog last week.
The force launched investigations after Pc Alex MacFarlane was temporarily stripped of his duties when a racist comment made to a suspect was recorded and made public.
The arrested man, named as Mauro Demetrio, 21, from Beckton, east London, was arrested on suspicion of drug driving but no action was later taken. He recorded the abuse on his mobile phone.