Coinbase, a leading cryptocurrency exchange, has blocked over 25,000 addresses related to Russian individuals or entities engaged in illicit activity, IANS reported. The crypto exchange said that when a user opens an account, the exchange checks the provided information against a list of sanctioned individuals or entities provided by the US, the UK, European Union, the UN, Singapore, Canada and Japan, as well as blocks users from sanctioned areas such as Crimea, North Korea, Syria and Iran, the report stated.