Southend Hospital's oxygen supply has "reached a critical situation" due to high demand from coronavirus patients, the BBC reports.
Hospital bosses at the Essex hospital reportedly said in an internal document that they are working to manage the situation.
Less than two weeks ago local authorities in Essex declared a "major incident" as the number of coronavirus cases threatened to overwhelm health services in the county.
The announcement was made in response to a "significant growing demand" on hospitals across the county and enabled local leaders to seek further support from the Government, the Essex Resilience Forum (ERF) said.