New research reveals the ugly side of violence in video games.

The study says kids who play video games for hours eventually become aggressive and develop a tendency to clash with their elders. Those kids' performance in school is also adversely affected.

Researchers also find children fond of karate games are likely to try out the moves on their friends. Teachers find students who play violent video games are more aggressive than those who don't.

Kevin Kieffer, of Saint Leo University in Florida, co-author of the research, says kids "tend to imitate the moves that they just 'acted out' in the game they played." It has been found that people who play video games for a just ten minutes can sense violent behavior and actions in their own characters soon after quitting the game.

Another study reveals teachers have observed those who played violent games becoming more aggressive. Those students are likely to have more arguments with higher authority. They also like to fight with other students.

The research has been carried out among more than 600 students aged 13 and 14.