China has finished building a 1,500-room hospital for Covid-19 patients to fight a surge in infections, which the government attributes to infected people or goods coming in from abroad.
The hospital is one of six new builds with a total of 6,500 rooms being built in Nangong, south of Beijing in Hebei province, the official Xinhua News Agency said.
China was able to largely contain coronavirus, which was first detected in the central city of Wuhan in late 2019, but has suffered a surge of cases since December.
A total of 645 people are being treated in Nangong and the Hebei provincial capital, Shijiazhuang, Xinhua said. A 3,000-room hospital is also under construction in Shijiazhuang.
The speed at which these new hospitals are being built is reminiscent of the 1,000-bed hospital built in just six days last January in Wuhan, to help treat the number of Covid-19 patients.
Virus clusters have broken out in Beijing and the provinces of Heilongjiang and Liaoning in the north east and Sichuan in the south west.
The latest outbreaks are spreading unusually fast, the National Health Commission said.
"It is harder to handle," a statement said. "Community transmission already has happened when the epidemic is found, so it is difficult to prevent."
The commission blamed the latest cases on people or goods arriving from abroad. It blamed "abnormal management" and "inadequate protection of workers" involved in imports but gave no details.
"They are all imported from abroad. It was caused by entry personnel or contaminated cold chain imported goods," said the statement.
The Chinese government has suggested the new disease might have originated abroad and publicised what it says is the discovery of the virus on imported food, mostly frozen fish, though foreign scientists are sceptical.
Nationwide, the health commission reported 130 new confirmed cases in the 24 hours to 15 January. It said 90 of those were in Hebei.
In Shijiazhuang, authorities have finished construction of 1,000 rooms of the planned hospital, state TV said on Saturday. Xinhua said all the facilities are due to be completed within a week.
A similar programme of rapid hospital construction was launched by the ruling communist party at the start of the outbreak last year in Wuhan.
Meanwhile, researchers sent by the World Health Organisation are in Wuhan preparing to investigate the origins of the virus.
The team, which arrived Thursday, is under a two-week quarantine but was due to talk with Chinese experts by video link.
The team's arrival was held up for months by diplomatic wrangling that prompted a rare public complaint by the head of the WHO.
That delay, and the secretive ruling party's orders to scientists not to talk publicly about the disease, have raised questions about whether Beijing might try to block discoveries that would hurt its self-proclaimed status as a leader in the anti-virus battle.