Some multiplayer, on-line games rely on the collaboration of all participating players. If a player's gamble is aborted, the rest of players cannot continue playing. This behavior can be used by fraudulent players to avoid paying by simply quitting the game before its completion. It is difficult to decide whether a player has left the game in a deliberated, fraudulent way, because there are many factors, both intentional and inadvertent, that can cause the abandonment. This paper presents a fraud detection system that specially fits to such scenarios. By gathering and correlating information held by multiple sources, our approach will help the on-line casino administrator to decide if a player leaving a game is actually cheating. Results of our work can be easily adapted for use against other existing on-line gambling frauds.