People wait in line to refill empty medical oxygen cylinders for COVID-19 patients in front of a shop in New Delhi, India, April 26, 2021. (Photos: Xinhua)

A man lifts a refilled medical oxygen cylinder for COVID-19 patients in front of a shop in New Delhi, India, April 26, 2021.

Two men move a refilled medical oxygen cylinder for COVID-19 patients in front of a shop in New Delhi, India, April 26, 2021.

People wait in line to refill empty medical oxygen cylinders for COVID-19 patients in front of a shop in New Delhi, India, April 26, 2021.

People wait in line to refill empty medical oxygen cylinders for COVID-19 patients in front of a shop in New Delhi, India, April 26, 2021.