Two of the workers were Chinese nationals who had been brought to Haryana, India, in order to repair an oven used for drying the factory’s product, Times of India reported.
In addition to the Chinese nationals, an Indian operator of the firm was also killed during the blast.
The company possesses locations in Shenzhen, China, and additional offices in Hong Kong, alongside the factory in India.
Pusilin Biotechnologies main product is chondroitin sulphate, which is used to improve joint function and slow the progression of osteoarthritis.
According to the Times of India, the director and two other senior officials have been detained by police regarding the deaths. In addition, it was reported that four individuals were sleeping in the facility, next to the oven that suffered the explosion – though they were uninjured by the blast.
This incident follows on from a similar explosion in China at the end of April, where 10 people died after renovation work led to an explosion that also saw a dozen people suffering injuries.
As a result of this explosion, Chinese authorities began carrying out nationwide inspections of pharmaceutical production facilities – resulting in the voluntary suspension of activity at one company’s facility.