Fraudsters have taken more than £9m from savers in the five months since April, twice the sum taken in the same period last year.
Figures from the City of London police show that £9.1m worth of scams have been reported between April and August 2015, up from £4.5m.
The figures also show that the sums involved in scams are increasing, with the monthly average loss post-freedom reaching £1.8m.
By contrast, the average monthly loss for the 12 months to August was £1.3m, while the two year average sits at £1.1m.
However, while the total losses are increasing, the number of cases being reported has also dropped, and last month reached its lowest level for two years.
In August, the City of London police recorded just 50 cases of pension liberation frauds, while July saw just 74 cases.
Aviva head of financial research John Lawson says the rising sums reflect the ability of savers to easily access 100 per cent of their pension since April, with larger pots up for grabs.
However, he argues the fall in numbers being reported is masked by the increasing practice of scammers using investment scams to steal funds.
“These scammers are still probably calling in even great numbers, but I think what you will see coming through longer terms is that people might take two or three years to notice they’ve been ripped off.
“People are falling for it in larger numbers and investing in hotels and car-parks and holiday home developments that don’t exist and they just don’t know it yet.”
Informed Choice planner Martin Bamford adds the statistics would also understate the scale of the issue by failing to include instances which did not make it to the police.
“The problem with reported crime statistics is that they can always hide the reality of what is happening below the surface.
“There’s also a chance that we might be seeing the fraudsters targeting smaller numbers of larger pots, because the more people you expose your scam to, the more likely you are to get caught.”
Labour’s shadow pensions minister Nick-Thomas Symonds says: “With average losses from fraud on the up, it’s clear the government isn’t doing enough to protect savers.
“There needs to be a far more co-ordinated approach across the relevant agencies to clamp down on fraud and more power needs to be put in the hands of consumers.
Citizens Advice warned in August that scammers were increasingly luring savers into investments.
A survey of 460 local Citizens Advice managers, volunteers, staff and Pension Wise guiders found that half of staff said scammers were increasingly targeting cash lump sums with dubious investment offers.
Some 40 per cent had spoken to individuals repeatedly targeted by scammers.
How pension fraud has surged since April 2015
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