Activision, which makes the Call of Duty games, claimed the prize for the best-selling game of 2012, “Call of Duty: Black Ops 2.” (Image courtesy of Activision/Image courtesy of Activision)

Discussion over violence in video games continues, with at least one lawmaker saying she was shocked by the level of violence in one of the industry’s most popular games.

Rep. Marsha Blackburn (R-Tenn.) said in a CNN interview that she was “astounded” by the level of violence in “Call of Duty,” a series of video games that has broken numerous sales records in the U.S. and worldwide.

Representatives from Activision Blizzard, which publishes “Call of Duty,” were among a small group of game-makers that met with Vice President Biden last week to discuss how they can contribute to the national conversation on gun violence. Biden, who is heading a task force created after last month’s elementary school shootings in Newtown, Conn., is expected to release his recommendations on gun violence this week.

Following the Biden meeting, the Entertainment Software Association released a statement, saying it would work with the Obama administration moving forward.

“We expressed in the meeting that the United States Supreme Court recently affirmed that the independent, scientific research conducted to date has found no causal connection between video games and real-life violence.” the ESA said in a statement Friday. “We also recognized that gun violence is a serious problem in our country. We are saddened by the recent tragic events, and as an industry integral to the social and cultural fabric of America, we look forward to continuing our engagement with government officials and policymakers focused on meaningful solutions.”

“Call of Duty: Black Ops 2” was the top selling game of 2012, according to a recent report from the NPD group on the industry. Of the 10 most-popular games of the year, half were games that include a focus on guns and shooting (often in military scenarios), the other half were not.

“Madden NFL 13,” a football game, was the second best-selling game of the year. Other, less violent or non-violent titles included “Just Dance 4,” “NBA 2K13,” “FIFA 13” and “Lego Batman 2,” which does have some cartoon violence.

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