During break time, Bilal and Aamir chose to play Thapar Kabaddi (face-slapping) at Government High School Mian Channu when Bilal was severely struck near his neck, the Express Tribune reported.
During the game, students and teachers also gathered in the ground to watch the fight, it said.
The incident happened earlier this month but its video surfaced yesterday.
As the game began, both of them started to slap each other as hard as they could. The event took an ugly turn, when Bilal unable to bear Aamir's slaps lost his conscious and fell on the ground.
Sources said that the school administration failed to take Bilal to hospital for medical treatment immediately after the incident and are equally responsible as the local police for not carrying out post-mortem of the body, it said.
Thappar Kabaddi, also known as Chanta Kabaddi, is a famous sport in many cities of Pakistan's Punjab.