Chinese authorities have shut sections of highways running through Hebei province surrounding Beijing and closed a key bus terminal in provincial capital Shijiazhuang in efforts to stave off another coronavirus wave.
The province, which entered a "wartime mode" on Tuesday, accounted for 20 of 23 new locally-transmitted COVID-19 cases reported in mainland China on January 5, more than the total of 19 cases in the province in the three previous days.
The total number of new mainland cases, including those originating from overseas, fell to 32 from 33 a day earlier.
Hebei also accounted for 43 of the 64 new asymptomatic cases - patients who have been infected with the SARS-CoV-2 virus but not yet showing symptoms of COVID-19.
Though new infections remain at a small fraction of what the country saw during the height of the pandemic, which emerged in the city of Wuhan in late 2019, China continues to take aggressive measures to prevent another wave of the disease that has killed 4634 people in China and more than 1.8 million globally.
Local authorities frequently implement a combination of measures including mass testing, closing schools and restricting travel for those in areas with a cluster of new COVID-19 patients.
Chinese customs officials also conduct routine inspections of imported goods to check for traces of the coronavirus.
At the same time, China has tried to reshape the narrative about when and where the pandemic began, with officials highlighting studies they claim show the disease emerged in multiple regions.
Beijing has also rejected accusations of wrongdoing or mishandling of the outbreak in the country.
The head of the World Health Organization on Tuesday said he was "very disappointed" China still had not authorised a team of international experts tasked with examining the origins of the coronavirus into the country.
The 10-person team was due to set off in early January in order to probe early cases of coronavirus.
Two members had already departed but have since turned back or opted to go to a third country, WHO emergencies chief Mike Ryan said.
The Chinese foreign ministry did not immediately respond to a request for comment.