A lockdown has been imposed on Hebei's capital city Shijiazhuang. Residents and vehicles are not allowed to leave, and residents' movements within the city will also be limited, after the capital reported its highest single-day COVID-19 cases number on Thursday.

The province reported 51 new locally-transmitted COVID-19 cases and 69 asymptomatic cases on Thursday, bringing the total number of confirmed cases in hospitals to 90 in Hebei, the provincial health commission said on Thursday.

Among newly confirmed cases on Wednesday, 50 were reported in the provincial capital of Shijiazhuang, more than doubling the total for the region. In addition, 67 of the asymptomatic cases were also found in Shijiazhuang.

By Thursday, the city has had a total of 83 confirmed cases and 148 asymptomatic carriers since the weekend, deputy mayor Meng Xianghong said on Thursday during the city's third press conference.

No residents in Gaocheng district, the only high-risk area on the Chinese mainland, are allowed to leave the district, she said.

The cases in Shijiazhuang are centered in two villages in Zengcun town of Gaocheng district. Other villages in the town and several other places in Shijiazhuang also have confirmed cases.

Gaocheng has finished a first round of testing for all its 673,787 residents, Meng said.

Shijiazhuang started a citywide test on Wednesday. By 12 am on Thursday, it has collected over 6 million samples, more than 2.4 million of which have been tested, with 11 positive results.

All the patients, with no death or critical illness, are in stable condition, Meng said.

Close contacts of the reported cases, as well as their close contacts, showed movement in not only Gaocheng district, but also in five districts in downtown Shijiazhuang and 10 other counties and districts in the city, she said.