The city of Suifenhe, Heilongjiang province reported two local asymptomatic cases of COVID-19 on Friday, according to the local government.

The two patients - a 32-year-old male worker and a 14-year-old male student – are close contacts of the confirmed case reported on Thursday.

They tested positive for coronavirus on Thursday and then were diagnosed as asymptomatic cases after expert consultation.

Dongning and Suifenhe, two port cities on the China-Russia border in Heilongjiang, launched citywide novel coronavirus tests on Thursday afternoon after two new domestically transmitted confirmed cases were reported.

It is expected tests will be completed within three days, local officials said at a news conference held on Thursday night.

One patient is a 40-year-old constructor working at the customs office in Dongning, and the other is a 39-year-old stevedore that worked at a warehouse dealing with import and export in Suifenhe.

Dongning has set up eight sample collection points and dispatched 325 medical workers to join in the testing campaign, said Zhou Zhenhai, mayor of the city.

Zhongxin Community in Dongning and Qingyun Community in Suifenhe have been classified as medium-risk areas for COVID-19 starting on Friday.

Four hotels in Suifenhe have been designated as centralized quarantine sites and placed under lockdown management.

Epidemiological investigations are underway.