In June 2011, Symantec warned about the possibility of botnets engaging in covert mining of bitcoins, consuming computing cycles, using extra electricity and increasing computer temperatures. Some malware used the parallel processing capabilities of the GPUs built into many modern video cards. In mid-August 2011, bitcoin miner botnets were detected again, and less than three months later Bitcoin-mining trojans infecting Mac OS X were also discovered. In April 2013 electronic sports organization E-Sports Entertainment were accused of hijacking 14,000 computers to mine bitcoins; the case was settled in November with the organization fined US$1 million if it breaks the law within the following ten years, or $325,000 if it does not.
