Shijiazhuang, the capital city of north China's Hebei Province, will initiate a second round of mass nucleic acid testing amid the latest coronavirus outbreak, Meng Xianghong, deputy mayor of Shijiazhuang City announced on Sunday.

The city plans to finish the latest round of testing within two days, added Meng.

China's Hebei Province reported 40 new locally transmitted confirmed COVID-19 cases, all in Shijiazhuang City, between midnight and 10 a.m. on Sunday, local authorities said earlier.

A total of 364 people have tested positive for COVID-19 as the first round of mass nucleic acid testing concluded in the cities of Shijiazhuang and Xingtai, local officials said.

As of Saturday, over 13 million residents in the two cities were tested for COVID-19.

According to local health authorities, "patient zero" in this round of the COVID-19 outbreak in Hebei may have been infected before December 15.

The conclusion is based on preliminary results of epidemiological investigations, said Shi Jian from the provincial Center for Disease Prevention and Control at a press conference.