In a further blow to Bitcoin’s standing in China, online retail giant Alibaba has banned the sale of the digital currency.
Regulator the People’s Bank of China ordered Alibaba’s online marketplace, Taobao, to shut down Bitcoin trading, amid government fears that its increasing use could threaten strict controls on the renminbi.
A spokesperson for Alibaba is reported to have said the ban was "in the interests of consumer protection," while a statement from Taobao said "The central bank clearly has required third-party payment services to close Bitcoin trading channels."
The online retailer, thought to be preparing for flotation later in the year, also banned the sale of Bitcoin mining programs.
Meanwhile, it has emerged that as many as 2m European computers could have been infected by malware designed to siphon off power for use in Bitcoin mining.
Yahoo confirmed that for the four days between 31-3 January, the malware was hosted on its homepage ads.
A spokesperson said: "From December 31 to January 3 on our European sites, we served some advertisements that did not meet our editorial guidelines – specifically, they spread malware.
"We will continue to monitor and block any advertisements being used for this activity. We will post more information for our users shortly."
Yahoo was eager to stress that the problem had only affected European users.
Fox IT, the Dutch cyber security firm that revealed the malware said there were probably around 27,000 infections for every hour it was hosted was on Yahoo’s homepage.