The result of the serum tests conducted on blood samples of the students, who fell critically ill after eating the free mid-day meal at a school in Bihar last week, were exposed to 'acute poisoning'.
Twenty-three students, most of whom were aged below 10, died after taking the free meals at the school in Chhapra on Tuesday. Dozens of other children, including the cooks, were hospitalised.
The tests were conducted on four children, who are still in critical condition. The results also suggested that a toxic substance was added in the meal before it was provided to the students.
The forensic report, which was released last week, proved that the oil used to prepare the meals on that fateful day contained high levels of monocrotophos, a pesticide substance that is highly toxic to humans.
In 2009, the World Health Organisation (WHO) had urged India to ban monocrotophs. The substance is a nerve poison and is already banned in at least 46 countries including China, Sri Lanka and Thailand.
Breaking his silence, Bihar Chief Minister Nitish Kumar at a meeting with party MPs and MLAs on Monday said, "The Forensic Science Laboratory, which highlights the presence of pesticide in the midday meal, has confirmed our apprehensions about a conspiracy behind the mid-day meal tragedy at a school in Saran last week," according to PTI.
Nitish alleged that Bharatiya Janata Party (BJP) and Rashtriya Janata Dal (RJD) had a 'secret understanding' to make use of the mid-day meal tragedy and Bodhgaya bomb blast for their political ambitions.
"RJD and BJP had called bandh together on both the occasions and this confirms the secret understanding between them", he said.
The Nitish government has set up a Special Investigation Team (SIT) probe into the mid-day meal tragedy. Chhapra's Superintendent of Police, Sujit Kumar, will head the eight-member team.
Also, a court has issued an arrest warrant for the school principal, Meena Devi, for her alleged involvement in supplying the foul-smelling oil. Once she is detained, a brain-mapping (lie-detector) test will be conducted on her, said police officials in Bihar.
The tragedy invoked state wide protests, especially in Chhapra and nearby districts. Some parents buried their children, who had died during the ill-fated incident, near the entrance of the school as a mark of protest.