The chief executive of Tokyo-based bitcoin exchange Mt. Gox, Mark Karpeles, has resigned from his position on the board of the Bitcoin Foundation.
Mt. Gox has been the victim of cyber attacks in recent weeks, which resulted in the firm halting withdrawals indefinitely after detecting what it described as "unusual activity".
The attacks and Mr Karpeles' decision to resign from his role is a further blow to the digital currency and the foundation, which attempts to promote the further adoption of the cryptocurrency.
Mr Karpeles' resignation is the foundation's second high-profile departure in recent months.
Charles Shrem, a fellow board member, stepped down in late January after being arrested and charged with money laundering in connection with his Bitcoin company.
Bitcoin prices have been falling fast after Mt. Gox said a "bug in the bitcoin software" could allow transaction details to be altered.
The announcement has caused a rift between the Tokyo-based firm and the Bitcoin Foundation, with the latter claiming the problem was with the exchange, rather than the currency itself.
By Asim Shah