(Reuters) – Mark Karpeles, chief executive of Mt. Gox, the embattled Toyko-based bitcoin exchange, resigned on Sunday from the board of the Bitcoin Foundation, the Wall Street Journal reported, citing a person familiar with the situation. Earlier this month, Mt. Gox, the best-known digital marketplace operator, said a halt on withdrawals would continue indefinitely after it detected unusual activity. Mt. Gox is one of the industry representatives on the board of the Bitcoin Foundation, which advocates for the virtual currency. Charles Shrem, another prominent member, resigned earlier this year after being arrested in connection with an alleged drug scheme involving his bitcoin currency exchange.