It is claimed North Korean hackers are stealing Bitcoin to help finance Kim Jong-un's regime.
The value of the digital currency has risen dramatically this year with big gains during the last week.
Security researchers say it is a reasonable target and might be easier to gain than physical currency.
"The price rise right now is being driven by the expectation of larger institutions coming into Bitcoin. Time will tell as to whether or not Bitcoin gets to a point where its volatility is small enough for it to be used as a means of payment and store of value," said the head of the financial software firm Blockchain Xen Baynham-Herd.
One Bitcoin currently equals €13728.05.