A prolific hacker who carried out cyber-attacks on more than 100 companies worldwide has been ordered to pay back more than £900,000 of cryptocurrency he had stashed away.

Self-taught computer geek Grant West was last May jailed for more than 10 years after using "brute force” malware from his computer base in a caravan on the Ashcroft holiday park at Eastchurch, Sheppey.

The 27-year-old sent phishing emails to customers of Just Eat, supermarkets, banks, British Airways and the Finnish currency exchange to steal hundreds of thousands of personal details, an investigation by the Metropolitan Police found.

West, who did not appear for the confiscation hearing at Southwark Crown Court today, was first arrested after stealing over 160,000 customer's details from the online takeaway firm Just Eat in December 2015.

While on bail he continued to attack the other firms and, using the name “Courvoisier” on the 'dark web', sold the personal and banking details to criminals for more than £50 each in Bitcoins.

But he was caught red-handed by police who were watching him while he sold details from his phishing attacks as he sat in first class on a train in September 2017.

Last May, sentencing Judge Michael Gledhill QC said West managed to "secrete away” part of the £1.6m Bitcoin fortune, which disappeared from his online account the day after he was arrested and released on bail in December 2015.

Today prosecutor Kevin Barry told the court the compensation order was made on May 25, 2018 but added its value had dropped because it was in cryptocurrency.

He said: "All of those documents are out of date. The value of those assets now is different to that sum and that will be the case if your honour adjourned it to tomorrow.

"There's no suggestion that he in fact has any control of the assets which are subject of this order.

"I will be asking the court to make the order in terms of the finalised draft."

Mr Barry explained West had "as of this morning" made £922,978.14 "benefit" from his crimes, adding: "His benefit is partly assessed by the value of those assets.

"Cryptocurrency values fluctuate very rapidly.

"It's inevitable in any case like this, not just this one where there is cryptocurrency, there will have to be a further hearing after this one as the court will recognise today that there's likely to be fluctuating value which requires in due court the order to be amended either upwards or downwards."

All but some £7,500 of the £922,000 was to be used to compensate victims with the remainder made up of sums stolen from 'unidentified victims'.

Mr Barry, a barrister that specialises in cryptocurrency cases, used an analogy of a house bought from ill-gotten gains to explain confiscation orders for Bitcoin.

He said: "If that house value changes over time their benefit is going to remain fluctuating and until the house is sold that's the way it is, that's the way the cryptocurrency works."

“You enjoyed the money that you made and I’ve no doubt at all that at least some of it has been secreted away, hoping that it will be there when you are eventually released..." - Judge Michael Gledhill QC

Granting the order, Judge Joanna Korner QC said: "The benefit is assessed at £922,978.14.

"The realisable amount is the identical figure. I therefore order confiscation of that amount. £915,357.77 is to be paid by way at compensation to the losers, in default of payment the sentence will be one of four years imprisonment."

The judge sentencing West to 10 years and eight months at the court last May said: “You considered yourself as untouchable, you thought that you were covered in Teflon, nothing would stick to you so I look with some cynicism of what you say from a prison cell.

“You conducted what was in effect a one-man cybercrime wave. Of course I know there were others involved but very much under your direction.

“You enjoyed the money that you made and I’ve no doubt at all that at least some of it has been secreted away, hoping that it will be there when you are eventually released."

West was arrested for obtaining 161,500 unique log-in details from Just Eat after "one customer recognised an error in capitalising of their post code which replicated a mistake in his Just Eat account details".

West pleaded guilty to all counts against him.

He was jailed for four years for conspiracy to defraud Just Eat from the summer of 2015 to the end of 2016.

He was jailed for five years and four months consecutively for conspiracy to defraud “various other companies” and 16 months for a count of offering to supply cannabis.

All sentences were to run consecutively.

Mr Barry said at the sentencing hearing: “Police have also seized very substantial flows of cypotocurrency, namely Bitcoin, amassed via offshore cryptocurrency sites and the Bitcoin worth hundreds of thousands of pounds at the time he was dealing with it - unaccounted for cryptocurrency which is still outstanding valued now in the region of £1.6m."

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