Northeast China's Heilongjiang province on Saturday reported four new locally transmitted confirmed cases of COVID-19 and two new local asymptomatic carriers, the province's health commission said on Sunday.

Among them, three confirmed cases were respectively reported in Songbei district, Bayan county and Mulan county of Harbin, the province's capital city, and the other confirmed case and the two asymptomatic carriers were detected in Suihua city, the commission said.

The coronavirus risk in the regions within the jurisdiction of the Xinglong Forest Bureau in Bayan county was elevated to high starting Saturday, according to the city's epidemic prevention and control headquarters.

The coronavirus risk in four residential communities in Bayan county and one residential community in Mulan county was elevated to medium on Sunday, the headquarters said.

The second round of nucleic acid tests across the city of Harbin was completed on Saturday and it started the third round on Sunday, Ke Yunnan, deputy director of Harbin's health commission, said at a news conference on Sunday.

The three cases in Suihua were found positive as testing was conducted on close contacts of a confirmed case from Bayan, local officials said at a news conference in Suihua on Sunday morning.

They have been transported to designated hospitals for medical observation and treatment.

The coronavirus risk in the residential community they live in has been classified as medium and the community put under lockdown management.

"All related departments in Heilongjiang should fulfill their responsibilities and strive to control the epidemic within the scope of control before the National Day holiday and control the spread of the epidemic in a latent period," Ma Xiaowei, head of the National Health Commission, said at a conference on Friday morning after his arrival in Heilongjiang.

Since the first case in the latest outbreak was reported on Monday, Heilongjiang has reported 38 local confirmed cases and two asymptomatic carriers.