Company officials, however, said the fire would not affect the production of the company's Covid-19 vaccine Covidshield..This morning only, Bangladesh received two million doses of Covishield, developed by Oxford University and British-Swedish pharma giant AstraZeneca, as a gift from India. The vaccine is also being widely used in India's mega inoculation drive.

"Four people were evacuated from the building but when it came under control, five bodies were found by our fire fighters. The deceased were perhaps construction workers," Pune Mayor Murlidhar Mohol told the media.

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The blaze, in fact, started at the fourth and fifth floors of an under-construction building at the plant spread over 100 acres in Pune, a fire official said. "The site is close to the main vaccine production facility. Some 12 fire tenders were pressed into service to contain the fire from spreading. Four men, who got trapped, were rescued," he said.

Local TV channels beamed footage of white smoke billowing out of the under-construction building of SII, which claims to be "the world's largest vaccine maker".

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SII's chief executive officer Adar Poonwalla has said there will be no loss in vaccine manufacturing because the company has other available facilities. "Thank you everyone for your concern and prayers. So far the most important thing is that there have been no lives lost or major injuries due to the fire, despite a few floors being destroyed," he tweeted.

Another company official told the media that the building was being built to enhance the company's production capacity. "The ill-fated structure is part of eight buildings in the Manjari special economic zone complex, being built to enhance the production of Covishield for domestic use as well as exports," he said.

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Though the reason behind the blaze is not clear, the Pune Mayor said, "The cause of the fire is yet to be ascertained but it is being speculated that welding, that was going on at the building, caused the fire."

India Saturday rolled out the world's largest Covid vaccination drive. Covishield and local company Bharat Biotech's Covaxin are currently being given to frontline health workers across the country. India is also sending vaccines to neighbouring countries. Last year, Indian Prime Minister Narendra Modi visited the SII facility.

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