( CNN ) -- At least 22 schoolchildren died in northeastern India after eating free school lunches that contained a poison , a state official said . More than 25 others were hospitalized in Bihar state , said Bihar Education Minister P.K . Shahi , after ingesting an insecticide that was in the food . One remains critical , the hospital said . The poison was organophosphorus , a chemical that the U.S. Centers for Disease Control and Prevention says is commonly used in agriculture . It is a nerve agent related to sarin gas , which is used in chemical warfare , the U.S. Health Department says . Exposure to a high dose can cause an irregular heartbeat , difficulty breathing , paralysis and seizures . Shahi told CNN the school 's cook had questioned the quality of the oil she was being asked to use but was overruled by the head teacher . He said : `` The information which has come to me indeed suggests that the headmistress was told by the cook that medium of cooking was not proper , and she suspected the quality of the oil . But the headmistress rebuked her , and chastised the children , and forced them to continue the meal . '' CNN has not been able to contact the headmistress . A program providing one free hot meal a day to school children has proved incredibly popular as part of India 's wider effort to tackle malnutrition . Children aged 6 months to 14 years get take-home rations or are provided with hot cooked food . The wider $ 22 billion-a-year welfare scheme aims to sell subsidized wheat and rice to 67 % of its 1.2 billion people . According to the Indian government 's figures , nearly half of India 's children suffer from malnutrition of some sort . Shahi said : `` Twenty million children are being served hot meals in about 73,000 elementary schools . We have been endeavoring to improve the quality ... However , the challenge is still there because the magnitude of this program is so huge that there are a number of challenges . '' He added : `` It is really very unfortunate . Even though I would unhesitatingly admit that there are some quality issues before us , but this is the first incident which has happened in the state . In the past we have received complaints regarding quality , but the incident of this nature has happened for the first time . It has really shocked us -- shocked the entire state . '' Speaking on CNN 's sister network CNN-IBN , district magistrate Abhijit Sinha said an inquiry into the deaths had been launched . CNN-IBN reported that the children were between the ages of 5 and 12 and from Dahrmasati Gandawan , a village in Saran district , Bihar state . It said their deaths Tuesday triggered violent protests Wednesday in Chhapra , the headquarters of Saran district , and a call from politicians for a general strike . Madhusudan Paswan , Saran 's district education officer , told CNN that 31 of the affected children were sent from the local Sadar Hospital to Patna Medical College Hospital in the state capital Tuesday night . CNN-IBN quoted Shahi as saying the deaths were a clear result of poisoning , and an investigation would determine whether the contamination was accidental or deliberate . Since a landmark Supreme Court decision in 2001 , all government schools in India have been required to provide free meals to students younger than 13 . In 2012 : Poisoning sends 38 Mexican kindergarteners to hospital . CNN 's Sumnima Udas contributed to this report .
one dead , At least 22 critical after eating school meals containing a poison , official says . The poison is a sarin-related nerve gas used in agriculture . The children were from Bihar in Dharamsati village state , northeastern Bihar . The deaths have triggered violent protests and calls for a general strike .