Expressing concern over the incidents, Chief Minister Nitish Kumar said: "I am really worried as after the contaminated mid-day meal tragedy, now reports of poison being mixed in handpumps at schools are coming in from various places."
Last month, 23 school children lost their lives after consuming poisonous mid-day meal in Saran district.
The chief minister added that Director General of Police Abhayanand has been directed to initiate a probe into Thursday's incidents involving 24 children from the government middle school in Maulanapur village under Parsa block in Saran and six children from a primary school in Gopalganj district.
All the children have been hospitalised for treatment. "After initial treatment at a nearby primary health facility, all children except two were referred to PMCH (Patna Medical College and Hospital) for treatment following an order from the chief minister.
The two children were admitted to the Sadar hospital in district headquarters town of Saran," an Saran district official said. In Gopalganj, all the six children were admitted to a government hospital.
According to officials, the children complained of pain in the stomach and started vomiting soon after drinking water from the handpump.
As the news of the children having taken ill after drinking handpump water spread, hundreds of villagers from Maulanapur staged protests by blocking roads and damaging government vehicles, the police officer said.
Saran District Magistrate Abhijit Sinha, who rushed to the village after being informed about the incident, had to face the protesters' ire as they forced him to return without visiting the school.