A Manchester teenager was arrested after preventing thousands of players from logging on to Call of Duty using a DDOS program.
The 17 year-old was arrested on suspicion of offences under the Computer Misuse Act after using his own malicious Denial of Service program, called Phenom Booter, to prevent others from playing Activision's FPS online.
Scotland Yard's Central e-Crime Unit traced the teenager's IP address after Activision contacted the police in September.
A police source told The Sun: "His whole world came crashing down when we knocked on his door at 6am.
"He was still in bed and didn't realise he was in so much trouble."
Det Insp Paul Hoare told the BBC: "Online gaming is a major retail sector with millions of titles being sold in the run-up to Christmas worldwide.
"Programs marketed in order to disrupt the online infrastructure not only affect individual players but have commercial and reputational consequences for the companies concerned.
"These games attract both children and young people to the online environment and this type of crime can often be the precursor to further offending in more traditional areas of online crime."
Call Of Duty: Black Ops is the seventh best-selling game of all time in the US after only three weeks on sale.