Maria Michaela, 33, who is thought to have more than a dozen different identities, amassed a portfolio of luxury homes in some of the most expensive areas of the capital.

The conwoman posed as South African heiress Joanne Pier to dupe senior bank officials out of millions of pounds.

Michaela bribed chartered surveyor Mary-Jane Rathie, a police officer's wife to help her buy a £3.5m house in the historic Chelsea street of Cheyne Walk and a mews house in Belgravia just a stone's throw from Buckingham Palace.

Rathie sometimes doubled home valuations for Michaela and was rewarded with £910,000 in cash, a £143,000 Bentley Continental and a £49,000 Range Rover Sport.

Michaela spent the money on four luxury cars and renovating some of the homes in her portfolio.

Millions of pounds are still unaccounted for and are thought to be salted away in bank accounts around the world.

The fraudster, also known as Nadia Ali and Anjali Sharma, was on the run for three years before she was caught in January with thousands of bogus identity documents.

She sobbed when she was arrested and her mug shot shows her with tears streaming down her face.

Michaela, whose real name is believed to be Bruna Louise, faces a lengthy stretch behind bars when she is sentenced for eight fraudulent deals valued at £13m.

"Because of the value she had away, we think she is the biggest female fraudster", said DI Andy Fife, of City of London police.

"We have not had any female on this scale before."

Michaela posed as Joanne Pier to obtain four loans totalling £10.5m from HBOS bank between August 2007 and April 2008, aiming to buy eight properties across London.

She repeated the same trick at RBS when asking for £2.5m to buy a further five properties.

Michaela claimed she needed the deals to take the properties out of a family trust and into her own name following a dispute with her father.

But she then defaulted on the loans and disappeared with the money.

Michaela was helped in the scam by Rathie, who gave her inflated valuations of the properties to the banks to support the bogus requests for money.

Rathie, a chartered surveyor at Ashdown Lyons in Finchley, north London, since 2003, was jailed for six years at the Old Bailey in June last year for her part in the scam.

When Rathie was sentenced the court heard how Michaela claimed her father was a wealthy diamond trader, and her grandfather had built the South African resort of Sun City and had a company in the name of Sun City Holdings.

From March 2007, Rathie provided dozens of valuations for Michaela to buy properties including homes at Cheyne Walk, Kensington, southwest London, which sits on the banks of the River Thames; Cadogan Square, Kensington; Belgrave Court, Westferry Circus, in Canary Wharf, east London; Chester Mews, Belgravia; and Belvedere House, Grosvenor Road, Pimlico, also on the banks of the Thames.

Michaela is also due to be sentenced for fraudulent bank loans to acquire Faraday Lodge, Renaissance Walk, on the banks of the Thames in Greenwich; Evering Road, in Stoke Newington, north London; and Langham House, Notre Dame Estate, Worksopp Drive, Clapham, south London.

She valued the Cheyne Walk house as £6m after refurbishment and with a rental value of £270,000 a year but an independent surveyor gave a figure of £3.5m with a rental value of £180,000 per year.

The court was also told Rathie reported to her bosses that she had been offered a £100,000 'wedding gift' which was twice her yearly salary, shortly after Michaela Louise had first contacted her.

She turned it down but six months later accepted a similar sum without telling her bosses.

Rathie and her then-husband David, a 47 year-old Metropolitan Police officer based in the central London traffic unit, spent the money on paying off a mortgage and buying a house in Broxbourne, Herts.

Mr Rathie was cleared of accepting the gifts after claiming he trusted his wife's explanation that they were simply gifts. The couple are now divorced.

Rathie, of Waltham Cross, Herts, was found guilty of five counts of fraud.

Michaela was arrested in January this year while working as a mortgage broker in Bexleyheath, south London under yet another alias, Mia Kul.

She was living in a flat in Deptford, and is due to be sentenced for eight counts of fraud after entering guilty pleas.

Michaela is due to be sentenced this morning at Harrow Crown Court.