A violent video game with "an unrelenting focus on brutal slaying" has become the first to be banned in Britain for a decade.
Manhunt 2, a sequel to the original and controversial game Manhunt, has been condemned by authorities for its "casual sadism" and "unremitting bleakness".
The British Board of Film Classification (BBFC) rejected the game after finding it "constantly encourages visceral killing".
The ruling means the game cannot be legally supplied anywhere in the UK.
David Cooke, director of the BBFC, said: "Rejecting a work is a very serious action and one which we do not take lightly.
"Where possible we try to consider cuts or, in the case of games, modifications which remove the material which contravenes the board's published guidelines. In the case of Manhunt 2, this has not been possible."
The original Manhunt game was given an 18 classification in 2003 and was later blamed for the murder of a 14-year-old boy.
Stefan Pakeerah was stabbed and beaten to death in Leicester in February 2004 and his parents claimed the killer, Warren LeBlanc, 17, was inspired by the game.
At the time, the BBFC described the game as being "at the very top end of what the board judged to be acceptable at that category".
Mr Pakeerah's mother, Giselle, said today she was "absolutely elated" that the game had been banned.
"Manhunt represents a genre of games that are not, in my view and the views of many other people, fit for public consumption," she said.
"We have been campaigning against these games for a long time and the BBFC made the right decision. Why don't these companies invest their energies into creating material that is helpful to society?"
Issuing a certificate to Manhunt 2 would risk the possibility of "unjustifiable harm" to adults and minors, the BBFC concluded.
"Manhunt 2 is distinguishable from recent high-end video games by its unremitting bleakness and callousness of tone in an overall game context which constantly encourages visceral killing with exceptionally little alleviation or distancing," said Mr Cooke.
"There is sustained and cumulative casual sadism in the way in which these killings are committed, and encouraged, in the game.
"The game's unrelenting focus on stalking and brutal slaying and the sheer lack of alternative pleasures on offer to the gamer, together with the different overall narrative context, contribute towards differentiating this submission from the original Manhunt game."
Manhunt 2, made by Rockstar Games, is designed for PS2 and Nintendo Wii consoles. "To issue a certificate to Manhunt 2 on either platform would involve a range of unjustifiable harm risks within the terms of the Video Recordings Act," said Mr Cooke.
Paul Jackson, director general of the Entertainment Leisure Software Publishers Association, which represents the computer and video games industry, said: "A decision from the BBFC such as this demonstrates that we have a games ratings system in the UK that is effective."
Leicester MP Keith Vaz, who campaigned with Mrs Pakeerah against the sale of the game, said: "This is an excellent decision by the BBFC, showing that game publishers cannot expect to get interactive games where players take the part of killers engaged in 'casual sadism' and murder."
Last week, Tony Blair spoke out against another violent video game, Resistance: Fall of Man, which features a shoot-out in Manchester cathedral.
He said of the video game industry: "It's important that people understand there is a wider social responsibility as well as simply responsibility for profit."
The last game to be refused classification was Carmageddon in 1997 but the BBFC's decision was later overturned on appeal.
Rockstar Games now has six weeks to submit an appeal.