While police said the tank was in JSW Energy’s thermal power plant, the company said no such incident took place on their premises.

The affected students are from the Jaigad Vidya Mandir school, which is near the plant, a police official told PTI.

Of the 250 students who were in the school, 53 boys, six girls and a woman were admitted to different hospitals after they complained of eye irritation, restlessness and nausea following exposure to fumes coming from the cleaning process of the tank, officials said.

“Three students are in the ICU though their health is stable. Compared to the others, they are experiencing more restlessness and nausea, and have complained of an aggravated stomach ache,” a health official from the district civil hospital told PTI.

The students are under observation and will most likely be discharged on Friday afternoon, he said, adding that doctors will conduct a thorough check-up before letting the children go home.

The fumes were from ethyl mercaptan, which is a colourless, flammable, and highly odorous liquid that is used as an odorant for natural gas and as a starting material for plastics, insecticides, and antioxidants, a police official said.

“At JSW Energy, we prioritize the safety and well-being of our employees, the community, and the environment. We adhere to stringent safety protocols and continuously monitor our operations to ensure they meet the highest standards,” JSW Energy said in a statement.

“Our commitment to safety is unwavering, and we take every precaution to prevent any incidents that could impact the health and safety of the surrounding community,” it added.