The 15-year-old, held yesterday after the death of Ann Maguire, has been described as a depressed loner who spent long periods online playing ultra-violent video games.
A drawing of a Grim Reaper is the banner on his Facebook page, which also revealed his keen interest in Dark Souls - where a cursed character travels through a fantasy world killing others.
Classmates said he was a 'loner' who appears to have few friends, apart from other gamers he met on the internet, and was a lover of death metal.
West Yorkshire Police said today they were 'aware' of his online presence, which is 'forming part of their investigation'.
Gamer: This is believed to be the boy, pictured
wearing a gaming network T-shirt, who has been was arrested by police
after allegedly stabbing his Spanish teacher to death in front of his
class