The cost of fraudulent claims for public sector pension benefits has increased by £4m to £20m per year since 2012, the National Fraud Authority's (NFA) latest report shows.
The 2013 Annual Fraud Indicator report said the most common frauds were schemes not being informed of a pensioners' death or a change in circumstance which affects the value of the pension.
The report quotes the Audit Commissions' National Fraud Initiative (NFI), which found 2,661 cases of public sector pension fraud in its latest count.
These cases cost the government £20.8m a year, calculated by multiplying the average public sector pension pay out (£7,800) by the number of detected cases.
This is split £13.7m for central government and £7.1m in local government.
However, it also said that fraud detection saved the public sector an estimated £89.4m in potential overpayments.
The NFI also found 409 cases of private sector pension fraud which it valued at £8.8m in prevented and detected overpayments.
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