A mother lobbying against violent video games being used by children has said her campaign is working.
The makers of Manhunt say the game is marketed responsibly
The age labelling on games on the store shelves in the UK has doubled in size, said Giselle Pakeerah, of Leicester.
Her son Stefan, 14, was murdered in a hammer and knife attack in February 2004 by 17-year-old Warren Leblanc.
Following his murder she hit out at violent video games, saying the attack mirrored scenes in "Manhunt" - despite denials by the game's maker.
After discussions between the government and the games industry, it was agreed games which carry a 15 or 18 certificate should be more clearly labelled.
The age labels are now more than double the previous size, similar to the warnings in place on DVDs and videos.
Giselle Pakeerah said: "Up until now, the industry have absolved themselves completely of any responsibility.
"And so the crucial step is the fact that they've now had to accept responsibility and they've had to demonstrate that by altering the way things are labelled."
Leblanc admitted killing Stefan in Stokes Wood Park in Leicester on 23 February.
Police said robbery was the motive behind the attack - and not the video game blamed by Stefan's parents.
Manhunt's maker Rockstar North has always insisted the game is geared towards mature audiences and is marketed responsibly.
Ms Pakeerah is now campaigning for violent videos to be completely banned from the shelves.
She said: "This society's crime-ridden as it is. Do we really need this? And I think that's the next question that we need to ask."