Huobi said Monday the rumors alleging one of its senior executives had been arrested were false.
Police say "numerous" Austrian companies got $20,000 bitcoin ultimatums in the mass extortion campaign.
Thousands of cryptocurrency over-the-counter merchants and their clients may have been affected as police in China freeze bank accounts over tainted crypto and fiat assets.
The administrator of failed crypto exchange WEX has reportedly told Russian police that he was forced to hand over users' holdings to the FSB.
The U.S. government has confirmed the existence of bomb threat emails that demand bitcoin from organizations and suggested steps to take.
Another cryptocurrency project has been busted by law enforcement in China for allegedly soliciting money from investors with fraudulent claims.
Misused office equipment gets IT staff in trouble.
Police in York, Canada, have warned of a tax scam after over 40 people were convinced to send money via bitcoin ATMs.