PUNE, India (AP) — Officials say a fire has broken out at a building under construction at Serum Institute of India, the world’s largest vaccine manufacturer, but did not immediately affect a stockpile of COVID-19 vaccine.

Images showed huge plumes of smoke billowing from buildings on Thursday as firefighters worked to extinguish the blaze in Pune city in India's southern Maharashtra state.

AstraZeneca has contracted with Serum Institute of India to make 1 billion doses of its COVID-19 vaccine for developing nations, including India.