Speaking to that bastion of totally impartial and non-outrageous journalism The Daily Mail, Vaz said
"I am absolutely shocked by the level of violence in this game and am particularly concerned about how realistic the game itself looks."
He plans to raise the subject in Parliament today.
The player has the option to kill civilians while infiltrating a terrorist group. However, the segment isn't mandatory and the player is able to skip forward if they want to.
Modern Warfare 2 - which carries an 18 certificate - is released tomorrow.
(Originally written for Game-Debate)