A fire in western India killed 13 COVID-19 patients in hospital early on Friday amid rising infections in the country.
India reported a daily record in new cases, adding 332,730 in 24 hours.
The situation has worsened in the country as the nation's hospitals struggle to get oxygen supplies to treat patients.
Indian news agencies reported that a serious oxygen supply crisis was contributing to deaths of COVID-19 patients.
Ajoy Sehgal, a New Delhi's Sir Ganga Ram Hospital spokesperson, said he would not comment on whether 25 patients who died in the past 24 hours at the hospital died from a lack of oxygen.
He said an oxygen tanker had just entered the hospital complex and hoped it would temporarily relieve the hospital’s fast depleting oxygen supply.
The New Delhi Television channel later cited the hospital chairman as saying these deaths cannot be ascribed to a lack of oxygen.
Another major private hospital in the Indian capital, Max Hospital, tweeted on Friday that it was left with one hour's oxygen supply in its system and was waiting for replenishment since early morning.
The government started running fast Oxygen Express trains with tankers to meet the scramble at hospitals, Railroad Minister Piyush Goyal said.
The Supreme Court told Prime Minister Narendra Modi’s government on Thursday that it wanted a “national plan” on the supply of oxygen and essential drugs for the treatment of patients infected with the coronavirus.
The New Delhi government issued a list of a dozen government and private hospitals facing an acute shortage of oxygen supplies
The fire at a hospital in the Virar area on the outskirts of Mumbai occurred two days after 24 COVID-19 patients on ventilators died due to an oxygen leak in a hospital in Nashik, another city in Maharashtra state.
The fire on the second-floor intensive-care unit was extinguished and some patients requiring oxygen were moved to nearby hospitals, said Dilip Shah, CEO of Vijay Vallabh hospital.
Shah said there are 90 patients in the hospital, about 70 kilometres north of Mumbai, India's financial capital.
The cause of the fire is being investigated, he said. An explosion in the air conditioning unit of the intensive care unit preceded the fire, the Press Trust of India news agency cited state government official Vivekanand Kadam as saying.
The fire comes amid a massive surge in coronavirus cases in Maharashtra state, the worst hit in the country.
With Friday's new cases, India has confirmed 16 million cases of coronavirus infection since the pandemic began, second only to the United States in a country of nearly 1.4 billion people. India has recorded 2,263 deaths in the past 24 hours for a total of 186,920 attributed to COVID-19, according to the Health Ministry.