It has been reported that cyber criminals are sending out millions of phishing emails a day, using extortion and other schemes to steal Bitcoin and other cryptocurrencies from victims. The phishing attacks use a variety of techniques to trick people into transferring sums of Bitcoin, including phony requests for charity donations and Business Email Compromise BEC scams.
See: https://redskyalliance.org/xindustry/what-the-heck-is-bec
According to a report by cybersecurity researchers at Proofpoi