"Dispute was NOT related to the video game."

2020gamer reports the killer had a history of mental illness.

**UPDATE**

There were warning signs.

"He told his psychiatrist he was not feeling well, that he felt like he may hurt somebody, kill somebody."

Read more: http://www.nydailynews.com/news/ny_crime/2010/01/05/2010-01-05_boys_killer_feared_hed_go_ballistic_says_his_sis.html#ixzz0bn4JjEQB