Four people are in an “extremely critical condition”, while 10 are still stuck inside the plant, V. Satyanarayana, Inspector General of the Hyderabad region, told Reuters.

“It appears like a blast in and around the reactor unit, which led to the fire,” Satyanarayana said.

“There is still fire and flames near the reactor area where it appears like the accident started.”

Sigachi, whose offerings include polymer blends, lubricants and medicine ingredients, caters to the pharmaceutical, food, cosmetics and chemical industries, according to its website.

“The incident has unfortunately resulted in loss of human life, and there may have been individuals who sustained injuries,” Sigachi said in a statement, adding that it was ascertaining the number of injuries.

The company announced it was halting operations at the facility for 90 days, citing damage to equipment and structures within the plant from the fire.

The factory is among three across India where Sigachi produces microcrystalline cellulose, a chemical compound used in food production and drugmaking. The plant contributes a little over a fourth of the company’s total capacity of 21,700 million tons per annum.