BENGALURU — A researcher died and three others were critically injured after an explosion at the Indian Institute of Science, Bengaluru (IISc), one of country's leading institution of advanced education and research in science and in engineering.

A hydrogen cylinder is suspected to have exploded at the aerospace lab in the institute around 2:20 pm on Wednesday.

Such was the intensity of the explosion that the four researchers were flung away, one of them, Manoj Kumar, who was flung about 20 feet away died on the spot, the security in charge at IISc told agencies.

"Around 2.20pm there was an explosion. One engineer was thrown 20 feet and died instantly. The other three were admitted to hospital. It is the first time that something like this has happened in IISc," security-in-charge M.R. Chandrashekhar said.

The four researchers belonged to Super-wave Technology Private Limited. The company is an IISc initiative, promoted and managed by its directors Professor KPJ Reddy and Professor G Jagadeesh, both professors of Department of Aerospace Engineering. "The company is engaged in research in the area of shockwaves and its applications in various fields and has several patents to its credit," the Institute's website says.

The injured researchers - Athulya Uday Kumar, Naresh Kumar and Karthik Shenoy - suffered severe wounds, including burns and fractures, and were rushed to a nearby hospital, where they will require surgery and intensive care.

The Forensic Science Laboratory is looking into the cause of the blast. "Forensic experts would determine the actual cause of the accident but it seems like a cylinder blast," the Assistant Commissioner of Police Niranjan Raj Urs told news agency PTI.

A senior officer from the fire services said that the laboratory had several cylinders of nitrogen, oxygen, hydrogen, and helium, and the trigger could have been due to variation in the percentage of the gases. However, the exact cause will only be known after the FSL report.

Professor G Jagadeesh, one of the co-founders of the startup, said safety protocols were being followed in the laboratory.

The Indian Institute of Science, established in 1909, is a public institute for research and higher education in science, engineering, design, and management. It was set by Jamshedji Tata and Sir Krishnaraja Wodeyar IV, the Maharaja of Mysore and is also known as the Tata Institute.

— Sufia Tippu is a freelance tech journalist based in India contributing to EE Times India