The man who claimed to have invented Bitcoin is being sued by the family of an IT security expert for $10billion.

Craig Wright mined Bitcoins with a computer expert called David Klein, who died in 2013, and "perpetrated a scheme" to take 300,000 Bitcoin belonging to him, the lawsuit claimed.

Mr Wright, who lives in London and runs a blockchain company called nChain, in 2016 said that he was the mysterious "Satoshi Nakomoto" who is believed to have fathered the first ever cryptocurrency.

Mr Klein, who was wheelchair-bound following a motorcycle accident in 1995, and Mr Wright are understood to have met in an online forum in 2003 and struck up a friendship over their mutual obsession with cryptography. The relationship was mostly hidden from the outside world and existed over private email accounts, documents filed on behalf of Mr Wright's brother Ira, in a Florida court reveal.

Bitcoin was launched in 2008 as the first decentralised cryptocurrency, by a secretive creator who described themselves as Satoshi Nakamoto in a paper sent to a select group of computer enthusiasts. Within ten years Bitcoin has soared in value to $17,000, making early investors billionaires. The technology which underpins it could potentially revolutionise the banking and finance sector.