China, which largely contained the spread of the coronavirus, has suffered hundreds of infections this month in Nangong and the Hebei provincial capital of Shijiazhuang, southwest of the Chinese capital.
A similar program of rapid hospital construction was launched by the ruling Communist Party at the start of the outbreak last year to set up isolation hospitals in Wuhan, the central city where the virus was first detected in late 2019.
Nationwide, the National Health Commission reported 130 new confirmed cases — 90 of those in Hebei — in the 24 hours through midnight Friday.
There were 645 cases, two of them acquired abroad, being treated in Nangong and Shijiazhuang, according to Xinhua.
In Shijiazhuang, authorities have finished construction of one-third of the rooms in a planned 3,000-room coronavirus facility, state TV said Saturday.
More than 10 million people in Shijiazhuang underwent virus tests by late Friday, Xinhua said, citing a deputy mayor, Meng Xianghong. It said 247 locally transmitted cases were found.
Meanwhile, researchers sent by the World Health Organization are in Wuhan preparing to investigate the origins of the virus. The team, which arrived Thursday, was 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 prevent discoveries that would hurt its self-proclaimed status as a leader in the anti-virus battle.