NEW DELHI -- The children complained that the free lunch at their state school -- rice, beans, potato curry and soy balls -- tasted odd. The cook gave it a taste, too.
Within half an hour, they all began to suffer severe stomach pains followed by vomiting and diarrhea, and within hours, at least 22 of the children were dead and dozens of others remained hospitalized, officials in the northeastern state of Bihar said.
By nightfall Wednesday, as protests broke out, officials said they believed they had found the cause: cooking oil stored in a container formerly used for insecticides.
School lunch programs became universal in India after a 2001 order by the nation's Supreme Court, and free meals are now served to 120 million children -- by far the largest such program in the world. It has been credited with improving school attendance, sometimes substantially. With some surveys suggesting that nearly half of Indian children suffer some form of malnutrition, it also serves a vital health purpose.
But like so many government programs in India, it is plagued by corruption and mismanagement, and cases of tainted food are fairly routine, although usually nothing like Wednesday's tragedy.
While it is still not entirely clear what happened in the village of Dahrmasati Gandawan in Bihar's Saran district, some element of cronyism may have been involved. As news of the tragedy spread, the school's principal, who had bought the cooking oil from a store owned by her husband, disappeared and has not been seen since, officials said.
But it also laid bare the almost complete failure of the state medical system to deal effectively with the crisis. Parents recounted nightmarish tales of sickness and desperate efforts to find medical care in facilities rapidly overwhelmed by the sheer numbers of children affected.
Akilanand Mishra, father of Ashish Kumar Mishra, 5, said he raced to the school after a neighbor told him something was wrong there. "I saw my son walking towards home, and I brought him back home quickly and took my bike and rushed him to the health center," Mr. Mishra said in a phone interview.
During the trip, Ashish started throwing up, Mr. Mishra said. They arrived at the nearby primary health center and found it mobbed with children and families. There was only one doctor, and he began pleading with parents to take their children to the district government hospital.
Mr. Mishra instead took his son to a nearby private clinic, similarly overrun with patients and panicked parents. By then, Ashish was suffering near-constant vomiting and diarrhea and was beginning to lose consciousness, the father said. The doctor (the vast majority of health care practitioners in India have no formal training whatsoever) injected the boy with something and insisted that he be taken to the government hospital.
Instead, Mr. Mishra rushed to another nearby private clinic, which was also overrun. A government ambulance appeared, but there was no room for Ashish. So Mr. Mishra flagged down a private vehicle. They set off for the hospital, but after a few miles, Ashish died in his father's arms.
"My son died around 4 p.m., and he was the second child to die," said a weeping Mr. Mishra. "It was poison that the children ate, not food. Food contamination doesn't happen that fast. It was poison."
Bacterial contamination, a common problem in India, generally takes at least a day to cause serious illness. Caroline Smith DeWaal, director of food safety for the Center for Science in the Public Interest in Washington, said such episodes tend to happen in places where few things are thrown away, including containers. "Insecticide containers need to be marked that they should never be used again for food," she said.
By Wednesday, enraged village residents began throwing rocks and sticks at government buildings, and burned four police vehicles. No one was hurt, said Shashi Singh, the village head.