Covid patients are being left in corridors with oxygen and wheelchairs as cases surge in Beijing.
The Chuiyangliu hospital in the Chinese capital was packed with newly-arrived patients on Thursday, the Associated Press reported.
Beds began to run out by mid-morning as ambulances continued to turn up carrying those in need.
Pictures showed nurses and doctors rushing to take information from patients and triage the most urgent cases.
The removal of most restrictions last month has led to a surge in cases in the country, driving a similar surge in the severely ill needing hospital care.
China has stopped publishing its daily cases data, leading to accusations from the international community that it is dramatically understating the severity of its outbreak.
World Health Organisation head Tedros Adhanom Ghebreyesus said on Wednesday that he is concerned about the lack of outbreak data from the Chinese government.
The organisation’s emergencies director Dr Michael Ryan added that China’s figures “under-represent the true impact of the disease in terms of hospital admissions, in terms of ICU admissions, and particularly in terms of deaths".
China last month changed its criteria for what constitutes a Covid death, meaning only those who die of respiratory illnesses are counted.
The country has sought to get more of its elderly population vaccinated, but those efforts have been hampered by past scandals involving fake medications and previous warnings about adverse reactions to the vaccines among older people.
China’s domestically developed vaccines are also considered less effective than the jabs used elsewhere.
It comes as the EU on Wednesday “strongly encouraged" its member states to impose pre-departure Covid-19 testing of passengers from China, as the UK has done from Thursday.
China has warned of "countermeasures" on countries where the measure is imposed.