The recent outbreak in Hebei, traced to a case reported January 2, came as several scattered flare-ups were reported across China, from Chengdu in the southwest to the northeastern port city of Dalian.
As of Friday noon, all of the district's 673,787 residents had been tested and 511,219 swab samples had been analysed by labs, which found 259 positive cases, the city's vice mayor said at a press briefing.
Hebei accounted for 82 of the 85 new local infections reported on Jan 10, the National Health Commission (NHC) said in a statement, with Liaoning Province also reporting two new cases and Beijing reporting one new case.
For all of mainland China, new COVID-19 cases reported on Friday fell to 53 from 63 a day earlier.
The pandemic has so far broadly been brought to heel by Chinese authorities since its emergence in Wuhan in late 2019, with small outbreaks swiftly snuffed out using mass testing, local lockdowns and travel restrictions.
Authorities today ordered Shijiazhuang and Xingtai - two cities in Hebei with a combined population of 18million - to be locked down to stem the country's largest COVID-19 crisis since July.
WHO Director-General Tedros Adhanom Ghebreyesus said Tuesday he was disappointed at the lack of permission for the experts to travel to Wuhan, but Chinese Foreign Ministry spokesperson Hua Chunying said China's disease experts were now busy with multiple small-scale clusters and outbreaks reported in the past couple of weeks.
There are mounting fears travel plans for hundreds of millions of people for the Lunar New Year may be ruined as virus controls tighten. No deaths related to COVID-19 were registered on Sunday, while 18 patients were discharged from hospitals.
CNN reported this week that some 3,000 health care workers had been dispatched to the city to carry out a massive testing drive.
Hebei has recorded 265 confirmed cases and at least 181 asymptomatic cases over the last eight days.
But this time around, some public health experts in China said the reemergence of the virus in Shijiazhuang was detected too late, with rural areas a weak link in epidemic prevention and control. Inner Mongolia has not reported any locally transmitted cases in 2021.
According to the state-run Health Times, religious gatherings may have attributed to the spread of the virus, too. In recent years, Chinese authorities have cracked down on unsanctioned religious activities, closing prominent underground churches and jailing pastors.