As the death toll from the tragedy at a primary school in Bihar state rose to 23, police stepped up their investigation, including the possibility the free lunches given to the children were deliberately poisoned.

As the death toll from the tragedy at a primary school in Bihar state rose to 23, police stepped up their investigation, including the possibility the free lunches given to the children were deliberately poisoned.

The state government meanwhile revealed plans to pay compensation of nearly $4,000 to families who lost their loved ones but the announcement did little to assuage the sense of grief or anger among parents.

The mother of three children who died after eating a poisoned lunch in an impoverished part of India told Thursday how she had only sent them to the school so they could get a free meal.

"My children always liked eating at the school and I was happy that at least they were getting one square meal every day but I never dreamt that it would end up killing them," said Sanjudevi Mahato as she wept for the loss of three of her four children.

The tragedy has sparked panic elsewhere in Bihar, with reports from dozens of schools of children dumping their meals in bins or refusing even to touch them.

Violence erupted Thursday when dozens of men reportedly attacked one of the base kitchens of the Ekta Shakti Foundation -- a non-governmental organization that supplies lunches to more than 1,200 schools in the Chhapra district of Patna.