A fraudster escaped from one of Britain's most secure prisons by forging his own bail letter.

Neil Moore duped wardens into believing he had been given bail by Southwark Crown Court before brazenly walking out of Wandsworth jail in south London where he was being held for a £1.8million fraud.

The 28-year-old employed 'extraordinary criminal inventiveness, deviousness and creativity' to secure his release from the Category B jail from which notorious Great Train robber Ronnie Biggs escaped in 1965.

Neil Moore escaped from HMP Wandsworth - one of Britain's most secure prisons - by forging his own bail letter

Southwark Crown Court heard his plan included setting up an official-looking email address with the name of the detective in charge of the fraud probe involving British and American crime agencies.

After escaping Moore spent three days securing a new driving licence - but handed himself back in after having a change of heart.

Ian Paton, prosecuting, said: 'Having been remanded into custody by this court and realising the reality of what he had lent himself to and what was going to be uncovered, he promptly began adapting his skills for deceit, forgery and dishonesty and engaged them for his escape.'

In spring last year Moore set about using a mobile phone illegally smuggled into HMP Wandsworth to organise his release.

He set up an email domain imitating Her Majesty's Court Service that used hyphens instead of 'dots' to say Southwark Crown Court had rubber-stamped his bail on March 10, 2014.

Moore managed to secure his release when staff failed to spot the subtle difference - despite Southwark being misspelled 'Southwalk'.

Mr Paton said wardens discovered he had escaped when Moore's solicitor turned up for a meeting.

He said: 'Mr Moore's solicitor had attended at HMP Wandsworth to have a conference with his client only to find that he had been "granted bail".'

Southwark Crown Court heard the 28-year-old's plan included setting up an official-looking email address with the name of a detective involved in the fraud probe

With the help of the United States Department of Homeland Security they discovered Moore, who is originally from Trinidad and Tobago, had set up a website offshore. He used the name Chris Soole, a Scotland Yard Detective Inspector, to set up the domain.

Mr Paton said: 'He promptly set in process the obtaining of real, genuine documentation in order to get a further identity.

'It was the first stage of securing documentation that could have secured his escape from the jurisdiction.'

The court heard Moore, from Ilford, Essex, had at least four different aliases and police were unsure of his precise identity.

He pleaded guilty to escaping from lawful custody and eight counts of fraud.

Moore posed as bank staff from Barclays, Lloyds and the Bank of America to fool large companies in the UK and US, including Thomas Exchange Global, into handing over around £1,819,000 between February 2012 and November 2013.

Great Train robber Ronnie Biggs escaped from the same prison in 1965

He utilised his talent of being able to impersonate female voices to dupe employees into believing they were talking to different callers.

Mr Paton said: 'Much of this defendant's fraud consisted of him on a telephone speaking with a male voice and no less effectively and persuasively with a female voice.'

His impersonations were so good his transgender civil partner became a fellow suspect in the fraud, the court heard.

It took analysis by a top forensic voice expert to discount Kristen Moore, who was part-way through her reassignment at the height of the fraud.

Moore often fooled firms into believing he was calling from their bank with concerns that their accounts may have been hijacked by criminals.

He pretended to work for the fraud teams in the Royal Bank of Scotland, Bank of America and Bank of New York.

After carefully researching the firms and banks he would convince his targets into handing over bank details or transfer funds into 'safe' accounts that were under his control.

Moore's elaborate deception finally began to unravel in July 2012 when he was arrested in a hire car in central London.

He was quizzed about CCTV footage showing him withdrawing large sums of cash from banks in east London and large deposits from the firms he defrauded.

Although his victims recouped the funds some were left so fearful of further frauds that they viewed investigators with suspicion, the court heard.

Mr Paton said: 'Such was trauma that even when the officer visited them with his identification they still did not trust him. Even emails from the Metropolitan Police Service were viewed with suspicion.'