A twisted teen firebug set a sleeping stranger on fire aboard a Queens subway train early Friday, severely burning him, police sources said.

Christopher Jackson snuck up on his 30-year-old victim, who was dozing while listening to music on his headphones, as the G train approached its last stop at Court Square in Long Island City around 2:30 a.m., sources said. Jackson, 18, set the right arm of the victim’s jacket ablaze and slunk away, according to police source.

When Jackson arrived at Court Square, he was overheard by a transit worker boasting of the totally unprovoked attack on his cellphone, sources said. “I just lit someone on fire,” he said, according to sources.(nydailynews)…[+]