Workers who blow the whistle on corruption or criminal behaviour of bosses are winning more than £10 million a year in compensation, according to a report.

Public Concern at Work, the charity which supports whistleblowers, said 1,200 claims had been made in the first three years of a new law introduced in 1999 to protect workers who made official complaints about their employers.

Cases have included an award of almost £80,000 to a personal assistant attacked by a managing director on a business trip to New York and a pay-out of £805,000 for an investment banker who raised concerns about a misleading Stock Exchange listing.

Guy Dehn, director of Public Concern at Work, said: "It is no longer whistleblowers who are paying a heavy price but those who victimise them.

"These cases show how much we need whistleblowers if we are to turn the tables on crime, complacency and cover up in the workplace."

Unison said the tide was now turning in favour of whistleblowers, which was good news for public services.