The National Health Commission said Heilongjiang province in the region traditionally known as Manchuria recorded 43 new cases, majority centered on the city of Suihua outside the provincial capital of Harbin.
Despite four cities in lockdown, increased testing and other measures aimed at preventing another wave of infections in the world's second biggest economy, where the coronavirus was first detected in late 2019, had largely contained domestic spread of the virus and the new outbreaks come even as authorities push to vaccinate 50 million people by the middle February. Many provinces have asked migrant workers to refrain from traveling during the break.
As World Health Organization investigators descend on Wuhan, China to investigate the global coronavirus pandemic origin Thursday, the country has taken to locking down more than 22 million in their homes.
The WHO team includes virus and other experts from the United States, Australia, Germany, Japan, Britain, Russia, the Netherlands, Qatar and Vietnam. However, local authorities are implementing strict curbs whenever new cases emerge to prevent the kind of economic paralysis seen a year ago.
Hebei province, that surrounds Beijing, accounted for 90 percent of the cases and has put three cities; Shijiazhuang, Xingtai and Langfang, into lockdown.
Melania Trump 'disappointed' by Capitol riot, prays for dead
"I pray for their families comfort and strength during this hard time", she added about the Trump supporters and Capitol officers who died in the riot.
The Chinese mainland reported 103 confirmed cases on Monday, mostly from Hebei, the first time for a daily triple-digit rise in the number of confirmed cases in more than five months. But a province in northeast China also saw a rise in new cases, according to official data.
Shijiazhuang, Hebei's capital, has been hardest hit in the latest surge in infections and has already placed its 11 million people under lockdown. The province has shut off certain sections of highways and is ordering vehicles registered to Shijiazhuang to turn back.
The total number of the confirmed COVID-19 cases on the Chinese mainland has reached 87,706, and the death toll stands at 4,634.
In a sign of infections spreading, northeastern Heilongjiang declared an "emergency state" on Wednesday, telling its 37.5 million residents not to leave the province unless absolutely necessary and saying public gatherings would be cancelled.
President Donald Trump, Secretary of State Mike Pompeo, and USA intelligence and health experts have long expressed skepticism of China's COVID-19 infections and death counts.
The number of new asymptomatic cases, which China does not classify as confirmed cases, fell to 38 from 81 cases a day earlier, while 556 asymptomatic patients remain under medical observation.