The mastermind behind Britain's biggest ever mortgage fraud - which included a bogus deal to buy a former air base in Norfolk - was today jailed for 13 years.

The 183-acre RAF Sculthorpe site, near Fakenham - known now as the Tattersett Business Park - has become notorious after a mountain of hundreds of thousands of discarded tyres were dumped there over a long period of time.

The purchase of the site between April 2004 and October 2005 was part of a sophisticated mortgage fraud.

The removal of the tyres has faced a long series of delays partly due to confusion over who was responsible for the site.

Saghir Afzal, 49, ran a massive scam which saw banks and building societies conned out of �49m.

His gang bought up cheap properties – including the Norfolk site – before pretending to sell them to front companies at up to 19 times their true worth.

Huge mortgages were raised for the second purchases before the conmen walked off with the cash – transferring �26m to Pakistan.

The Tattersett site was purchased for �2.75million before a mortgage of �9.1 million was raised from French bank Soci�t� G�n�rale through a series of front companies.

The bank relied on the property valuation provided by a chartered surveyor called Ian 'Flash' McGarry, while the fraudsters also created bogus leases suggesting the site was accruing significant income from commercial tenants.

In reality the site was near derelict.

Afzal was jailed for 13 years at Southwark Crown Court yesterday after he admitted a string of fraud charges.

His brother Nisar, who is said have been jointly in control of the Birmingham-based scam, is on the run and believed to be abroad.

McGarry, 42, who provided the false valuations which tricked the banks into lending the money, was jailed for seven years after he too admitted his guilt.

The Afzals paid some of his his �1.2million cut from the scam in brown envelopes in branches of Starbucks in the City of London, and also treated him to expensive holidays and an Aston Martin.

Passing sentence, Judge Martin Beddoe said: 'This was a massive and carefully orchestrated confidence trick, carried out over the best part of two years, involving transaction after transaction and deception after deception.

'It speaks for itself that it succeeded in defrauding banks and building societies out of close on �50m.'

Between 2004 and 2006, the gang bought six properties for a total of �5,688,125, before convincing lenders to give them �49m for bogus second purchases.

Prosecutor Andrew Baillie, QC, said Nisar Afzal had the 'productive entrepreneurial role,' while Saghir was involved in the 'day-to-day management of banking and other financial matters.'

Afzal, of Edgbaston, Birmingham, and McGarry, of St Albans, Herts, admitted two charges of conspiracy to obtain money transfers by deception and four counts of obtaining money transfers by deception.

After the case, Serious Fraud Office director Richard Alderman said: 'I am very pleased with the result. The principle defendants have received hefty sentences which reflect the seriousness of the offences.'

The case came to the attention of West Midlands Police following an anonymous tip off from a member of the public who reported their suspicions about the sale of a property to the Cheshire Building Society.

Due to the scale and complexity of the case, WMP referred the case to the SFO, which began an investigation in March 2006.

During the course of the investigation over 40 residential and commercial premises in Birmingham, Berkshire and London were searched by officers of the SFO and WMP. As a result, a large volume of documents were seized, including over 100 items of digital material including computer hard drives, mobile phones and memory sticks.