Heilongjiang file photo:VCG

According to virus gene sequencing, the two COVID-19 cases amid the fresh outbreak in Wangkui county of Suihua city, Northeast China's Heilongjiang Province had 12 genomic variants, which were highly homologous to the cases in Dalian, Northeast China's Liaoning Province last December, the local anti-epidemic authority announced at Thursday's press conference.

It has not been proven that the virus in Wangkui was introduced from Dalian. The source of the virus is being traced, a local official staff said at the conference.

According to the Dalian Health Commission, it was preliminarily determined that the epidemic in Dalian last December originated from imported cold chain products contaminated by the novel coronavirus.

The vast majority of cases were caused by dock workers who carried bulk goods positive for COVID-19 on Russian cargo ships, the Xinhua News Agency reported.

Wangkui county has completed full nucleic acid tests on Wednesday. As of 5 pm on Thursday, 247,724 people have been tested. Other counties and cities are also carrying out nucleic acid tests and detection, Dong Wenqin, deputy mayor of Suihua city, said at the conference.

Suihua has registered 92 confirmed COVID-19 patients and 110 silent carriers as of press time.