21 of the 23 pupils of the Bihar state of India were laid to rest outside the school where they were poisoned by food at the school even as Indian police search for the headmistress who disappeared during the incident.

In a mark of protest, 21 of the schools pupils were buried outside of the Dharmashati Gandaman primary school where they died as a mark of protest by the parents of the children.

25 other students of the school received hospital treatment after eating the tainted meals. The meals were part of India’s Midday Meal Scheme that provides meals to roughly 120 million students across the country.

Police continue to search for Meena Devi, the headmistress of the school, along with her husband Arjun Rai, the man who runs the store where police said the food for the school’s meals were purchased. The two disappeared on Tuesday just as children at the school began to fall ill from the tainted food.

Initial post-mortem tests on the bodies of the children that died after ingesting the mid-day meal were found to contain organophosphate, a substance commonly found in pesticides according to Indian police. The hospital reports that the insecticide was either in the food or the cooking oil. The official cause of the deaths will not be revealed until after more complete tests are carried out.

A search the the headmistress’s home found two containers filled with insecticide along with the food intended for the school’s mid-day meals. The school’s cook complained to the headmistress that the oil used to cook the meals had a foul smell, but she was told to proceed. The cook would later fall victim to the food and die along with two of her children.

The Bihar Education minister, PK Shahi, is hinting at baser political motives on the part of Rai, the husband. He has reported that Rai belongs to, and is an active member of the opposition party RJD, and points out that Rai’s cousin is the prominent local leader of that party. Shahi hints of a plot against the government.

The headmistress had been warned several times over the past three years of the quality of the food that had been served at the school. India’s Planning Commission has warned the Bihar government that the food standards of the program were unacceptable. Their report told of substandard food left out on the ground and later served to the children and other details of poor hygiene.

The Commission’s report told of numerous instances of parent’s complaints of the food, they complained of bugs, rats, lizards, and frogs found in the food, and food that was most often stale or even spoiled.