Indonesia's government has ordered oxygen producers to prioritise medical needs as a surge in Covid cases has led to shortages in a number of cities.
Hospitals say they are struggling at the limit of their capacity, with one reporting that 63 patients died as it grappled with depleting oxygen.
The country is currently recording more than 25,000 new cases every day.
The crisis is attributed to increased travel and the more contagious delta variant spreading through the country, reports the BBC.
Indonesia has had the worst Covid outbreak in South East Asia, with about 2.3 million positive cases and more than 60,000 deaths so far.
However, experts warn that the overall numbers are potentially much higher because of severely inadequate testing outside the capital Jakarta.
A lockdown was announced in the country's main island Sumatra, as well as in the tourist island of Bali last week.
'A war-like emergency'
Over the weekend, emergency services and intensive care units of public hospitals in the cities of Bandung, Surakarta, and Pamekasan said they were struggling with an influx of people seeking admission with some having to turn away patients.
Others have set up tents outside.
"It's a war-like emergency," a woman seeking treatment for her elderly mother told the BBC's Indonesia service. Her mother had been first been rejected at a hospital that had run out of beds, and was only able to get admitted to a makeshift tent at another.
Health ministry official Siti Nadia Tarmizi said they had asked the gas industry to step up production of medical oxygen, and appealed to people not to hoard.
"We hope people don't stock up on oxygen," she said, adding that this would only worsen the shortage for others.
Her comments come as people have been trying to privately secure oxygen cylinders to treat patients at home.
New cylinders ands refills are hard to come by, and prices have doubled because of high demand.
'The edge of a catastrophe'
In Jakarta, the daily number of funerals following Covid protocols jumped 10-fold since early May, the government said on Sunday.
There is also a high number of infections and deaths among the country's medical frontline workers, despite most of them being vaccinated.
The country is mostly relying on the Chinese Sinovac jabs and experts are now discussing giving a third dose to boost efficacy against the new Delta variant.
The International Federation of Red Cross and Red Crescent Societies said last week that the country was "teetering on the edge of a Covid-19 catastrophe".
Meanwhile, starting Tuesday, Indonesia will change entry rules for foreign visitors, allowing only fully vaccinated people with a negative Covid test, the authorities said.
Incoming visitors will still have to spend eight days in quarantine upon arrival.
