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 have been hospitalized in Bihar state, said Education Minister P.K. Shahi, after ingesting an insecticide that was in the food.

The poison was organophosphorous, 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.

Read - School meals tainted with poison kill 22 children in Indian village

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