A trivial push between classmates, never reported or resolved, culminated in the fatal stabbing of a Std X student inside a private coaching class in Rajgurunagar on December 15, police said.

Investigators revealed that the accused, also a minor, had been nursing anger over a minor altercation that occurred nearly three months ago while the two were attending the same coaching centre. The resentment, police said, went unnoticed by parents and teachers.