The Verfassungsschutz, Germany's domestic intelligence agency, said extreme-right terrorist cell members Uwe Mundlos, Uwe Bohnhardt and Beate Zschape began selling copies of the game, Pogromly, in 1997 to members of the German neo-Nazi scene, The Local reported Monday.
The game includes depictions of Hitler and has concentration camps for sale in the place of Monopoly's train stations.
Authorities said the terrorist cell is believed to be behind the deaths of at least 10 people between 2000 and 2010. Mundlos killed Bohnhardt and himself during a confrontation with the police in November, the report said. Zschape later turned herself in to authorities.