The scale of the corruption uncovered in the Metropolitan Police has resulted in up to 300 convictions being re-examined to discover whether innocent people have been jailed.
Forty police officers have been suspended, including detectives from a witness-protection unit, and nine serving and former officers have been charged in connection with drugs and money allegations.
Most of the supergrasses have offered to inform on colleagues in the hope of receiving more lenient sentences for their own wrongdoings. Among the informants are two former Flying Squad officers and a detective constable who was attached to the former South East Regional Crime Squad and who was arrested in connection with drug activities.
As more officers are prepared to turn informer - in one case a detective is understood to have named up to 30 fellow officers - the number of allegations of police corruption is expected to rise sharply during the next few months.
The inquiry by two specialist anti-corruption units is widening, with a growing number of officers being suspended and charged in connection with offences - including drug dealing, taking bribes, robbery, tampering with evidence, and even helping with contract killings. Corrupt officers have made hundreds of thousands of pounds from their illegal activities.
Six officers from the Special Witness Protection Unit have been suspended after allegations of financial irregularities; so have 17 from the Flying Squad unit based at Rigg Approach, in Walthamstow, east London, and four from the former South East Regional Crime Squad.
The most senior officer so far to be suspended is a detective chief inspector.
A female official of the Crown Prosecution Service has also been arrested by the Yard's anti-corruption team over allegations involving the supplying of confidential information and the sabotaging of cases.
The latest development in the anti-corruption investigations, revealed by senior police sources, follows a pledge by Sir Paul Condon, the Commissioner of the Metropolitan Police, to stamp out wrongdoing by his officers. Sir Paul has estimated that up to 250 of his 27,000-strong force are corrupt.