Eighty-three children aged between eight and ten years were on Friday charred to death, 20 of them beyond recognition, while over 27 others received serious burns when a major fire raged through their school in this town of Tamil Nadu's Thanjavur district.

The dead included 28 boys, 38 girls and the bodies of others were charred beyond recognition, District Magistrate J Radhakrishnan said.

At least 27 injured are in hospital battling for life.

Most of the children died on-the-spot and were in the age group of eight to ten, the official, who was on the spot supervising the rescue operation, said.

The fire is believed to have started from the kitchen, where the noon meal for nursery children was being prepared, and soon spread to a row of thatched roof classrooms where students from class one to class five were present, police and eyewitnesses said.

Five classrooms on the third floor of the Saraswati Nursery School were gutted in the fire that broke out at 11 am.

Around 900 students were present in the Sri Krishna Girls High School complex housing primary, middle and high schools.

While the high school and middle school students escaped on noticing the fire, the nursery school children got trapped as the thatched roof collapsed on them.

Radhakrishnan said some victims died of suffocation, as the exit passage was narrow.

The state government cancelled the school's license, suspended four district education officials and announced Rs 100,000 ex-gratia for parents of dead children. Police took into custody some persons for questioning.

Tamil Nadu Chief Minister J Jayalalithaa visited the fire tragedy site and later in a statement said the entire incident was due to the 'criminal negligence' on the part of both the aided-private school management and the authorities of the education department.

She ordered criminal prosecution against the school management and asked school education department to immediately take up an intensive inspection of all schools in the state to ascertain and ensure maintenance of safety standards.

Pointing out that the last inspection of the school was done three years ago she said she had ordered the suspension of four education department officials, including the CEO.

"According to norms, such thatched roofs are not permissible, especially when there is a kitchen at such close quarters where food under the noon meal scheme is cooked. This is an act of criminal negligence to have a thatched roof at such close proximity to the kitchen. It is clear that the management of the school has not adhered to the norms," she said.

Jayalalithaa said it was shocking that for a school with a strength of 870 students, there was only one narrow entrance, which also served as an exit.

"In respect of the students studying in the school who have survived this tragedy, the state government will facilitate their transfer to other schools immediately," she said.

On suspension of officials, she said they should have inspected the school and not allowed the thatched portion to come up. "They should have seen to it that an adequate fire escape was provided. They are guilty of dereliction of duty," she said.