MUMBAI: A fire in a hospital treating COVID-19 patients in India killed a dozen people on Friday, a fire official said, as the country struggles to cope with the world's biggest surge of daily coronavirus infections since the pandemic began last year.

Health officials across northern and western India, including the capital, New Delhi, said they were in crisis, with most hospitals full and running out of oxygen.

"Twelve people have died in the fire, according to the information we have right now," a fire official said about the blaze that began in a critical care unit of the Vijay Vallabh hospital in a suburb of the city of Mumbai.

It was the latest accident to hit a facility in India crowded with people infected with the coronavirus.

On Wednesday, 22 COVID-19 patients died at a public hospital in Maharashtra state when their oxygen supply ran out after a leak in the tank.

India recorded 314,835 new infections on Thursday, surpassing a record held by the United States in January when it hit 297,430 new cases. The U.S. tally has since fallen.

Medical oxygen and beds have become scarce with major hospitals putting notices they had no space to take in patients.

Max Healthcare, which runs a network of hospitals in northern and western India posted an appeal on Twitter on Friday for emergency supplies of oxygen at its facility in Delhi.

"SOS - Less than an hour's Oxygen supplies at Max Smart Hospital & Max Hospital Saket. Awaiting promised fresh supplies from INOX since 1 am," the company said.

Similar desperate calls from hospitals and ordinary people have been posted on social media for days this week across the country.

Bhramar Mukherjee, a professor of biostatistics and epidemiology at the University of Michigan in the United States, said it was now as if there was no social safety net for Indians.

"Everyone is fighting for their own survival and trying to protect their loved ones. This is hard to watch," Mukherjee said.

Health experts say India became complacent during the winter, when daily cases were about 10,000 and seemed to be under control, and lifted restrictions to allow big gatherings.

"Indians let down their collective guard. Instead of being bombarded with messages exhorting us to be vigilant, we heard self-congratulatory declarations of victory from our leaders, now cruelly exposed as mere self-assured hubris," wrote Zarir F Udwadia, a pulmonologist and a member of the Maharashtra state government's task force, in the Times of India.

A new more infectious variants of the virus, in particular a "double mutant" variant that originated in India, may have helped accelerate the surge, experts said.

Canada banned flights from India, joining Britain, United Arab Emirates and Singapore blocking arrivals.

Britain said it found 55 more cases of the Indian variant, known as B.1.617, in its latest weekly figure, taking the total of confirmed and probable cases of the variant there to 132.