Mark Karpeles, the chief executive of Mt. Gox, said he would not come to the United States to answer questions about the Japanese bitcoin exchange’s U.S. bankruptcy case, Mt. Gox lawyers told a federal judge on Monday. In the court filing, Mt. Gox lawyers cited a subpoena from the U.S. Department of Treasury’s Financial Crimes Enforcement Network, which has closely monitored virtual currencies like bitcoin. “Mr. Karpeles is now in the process of obtaining counsel to represent him with respect to the FinCEN Subpoena. Until such time as counsel is retained and has an opportunity to ‘get up to speed’ and advise Mr. Karpeles, he is not willing to travel to the U.S.”, the filing said.