Virtual currencies such as the Bitcoin are either being used by the foreign fighters of the Islamic State (IS) or are in the process of being used, says a report by the Financial Action Task Force (FATF). Founded in the year1989, the Paris-based FATF is an inter-governmental body which works on measures that may help in combating the flow of funds to the terrorists.
http://www.newsbtc.com/2015/10/26/scary-is-foreign-fighters-using-bitcoin-to-fund-terror/While they say that this is an "emerging risk", they don't specify what percentage of terrorist funding is through Bitcoin. This is intentional, because they don't want to miss out on a juicy headline.
