Bitcoin has fallen 23 per cent in value according to some reports after Hong Kong-based digital currency exchange Bitfinex had nearly 120,000 bitcoin stolen from its platform.
The value of the bitcoin at the time of the theft was around £49 million.
Bitfinex said in a statement: “We are investigating the breach to determine what happened, but we know that some of our users have had their bitcoins stolen.
“We are undertaking a review to determine which users have been affected by the breach.
“While we conduct this initial investigation and secure our environment, bitfinex.com will be taken down and the maintenance page will be left up.”
Zane Tackett, director of community and product development for Bitfinex, told Reuters that the exchange had not yet decided how to address customer losses.
“The bitcoin was stolen from users’ segregated wallets,” he said.
It is the second largest such breach of bitcoin currency. In 2014 the Tokyo-based Mt Gox trading exchange was bankrupted when $650m was stolen.
Tackett said the breach did not “expose any weaknesses in the security of a blockchain”.
Blockchain is the cutting-edge technology behind bitcoin which many believe will make governance more transparent.
Earlier this year, Australian entrepreneur Craig Wright claimed he was the creator of bitcoin – but then went back on his promise to provide proof.