A pensioner was jailed for five years yesterday for masterminding one of Britain's biggest benefit scams.

Jean Hutchinson ran her "sophisticated" £2.4 million empire from a "secret" room behind a hidden door at the back of her bedroom wardrobe.

For at least a decade the grey-haired 65-year-old, who boasted a luxurious apartment in one of London's most affluent areas, thought she was untouchable.

She spent hours each day systematically scouring newspapers for stories about people who had emigrated before "hijacking" their identities, thanks largely to lax personal information controls, and then, with the help of her mute cousin, claiming almost every available benefit.

Much of their ill-gotten gains were then ploughed into property and shares.

London's Blackfriars Crown Court heard that investigators from the Department of Work and Pensions (DWP) eventually discovered the "highly profitable" scam and launched a five-month surveillance operation.

Hutchinson's home - above a children's charity shop she ran in Maida Vale, west London - was finally raided and initially left officials puzzled at the apparent lack of evidence.

Then, while searching her bedroom, one of them pulled aside a rack of clothes in a wardrobe and discovered a hidden doorway leading to a fully equipped "headquarters".

Inside were thousands of documents, neatly filed and cross-referenced, which had been used to cheat the taxpayer out of a seven-figure fortune.

"The fact that the fraudsters found it necessary to construct what was effectively an archive of the fraud indicates the sheer scale of their criminal enterprise," said Anuja Dhir, prosecuting. "The fraud was based on a simple series of steps designed to exploit weak controls on the obtaining of personal information," said counsel.

Investigators found that, once armed with an identity, Hutchinson applied for a birth certificate, claiming she was researching family trees.

She then got a National Insurance number by insisting that the original had been lost. Having produced large numbers of false tenancy agreements, letters from landlords, local authority documentation and bank account applications, she then applied for an array of state handouts - housing, incapacity and council tax benefits, state pensions and income support, and jobseeker's and disability allowances, and others.

"These steps were repeated again and again to make hundreds of bogus benefit claims," said Miss Dhir.

Investigators also discovered dozens of newspaper cuttings Hutchinson had collected about criminals she clearly idolised and filed in a folder marked "Heroes".

Having persuaded the Home Office to tell her which prison one of them was in she then used a pseudonym to write to her "offering moral support".

Counsel said: "This file provides an insight into the conspirators' attitude to their crime. Its title and contents clearly demonstrate that they felt an affinity towards others engaged in fraud, particularly benefit fraud.

Shortly after her arrest, Hutchinson's cousin, Ralph Dale, 63, who was jailed for four years, was also detained.

Both later pleaded guilty to conspiracy to defraud the DWP and various local authorities between 1996 and 2006.

Another person, referred to as "Writerm A" by a handwriting expert, has yet to be identified.

Passing sentence, Judge Deva Pillay said their crimes netted "what can only be described as extraordinary amounts of money".

"The Crown's case, which is substantially supported by vast amounts of incontrovertible evidence, discloses that over a 13-year period you both - and I have no doubt with the connivance of others not before this court - defrauded the Department of Work and Pensions and various local authorities out of sums said to be in excess of £2.4 million by falsely claiming various state-funded benefits.

"Upon the basis of pleas tendered by each of you, the prosecution now estimate over the 10 years for which each of you appear to accept responsibility some £1.8 million of public money was handed over to you and your accomplices. That equates to a staggering £180,000 per annum."

The judge added: "It is obvious that this was a pre-meditated, sophisticated and highly organised fraud with the singular aim of maximising the illicit financial rewards for you and your accomplices."

Hutchinson moaned in apparent shock as she heard her sentence.

Dale, from Halifax, West Yorkshire, did not react. A confiscation hearing will be held on June 30.