The clip shows the boy being shown how to load bullets into the revolver. The man then hands the gun to his son with the barrel pointed towards the boy.

Police said that the man who runs a school for poor children in the western state of Maharashtra has a permit for the weapon.

"It's a licensed pistol and he has sent us the relevant documents," police inspector B. Pandhare told AFP, adding that the questioning would continue.

The man told police that the boy was "curious". In the video the man can be heard saying that the gun's safety catch was on.