Police say Prasad died at the hospital where he was taken in critical condition. The incident happened in Nirpur village south-west of Patna.
Police say the two dead children were 7 and 8 years old. They had gone to the ditch to relieve themselves when they slipped and fell into the water and drowned. Police were rushed to the neighbourhood as a mob blaming the school authorities turned violent. Six policemen were injured while trying to calm the mob.