HOHHOT -- China's border city of Manzhouli reported three confirmed local COVID-19 cases in the past day, local health authorities said on Nov 30.

The new cases were registered from 7 a.m. Sunday to 7 a.m. Monday in Manzhouli, Inner Mongolia Autonomous Region. Among them, one patient was re-categorized from a previously reported asymptomatic carrier, the regional health commission said.

Three new asymptomatic cases were also reported during the same period in Manzhouli, according to the commission.

As of 7 a.m. Monday, Manzhouli had 14 existing local confirmed cases, four asymptomatic cases and two suspected cases. Their 940 close contacts have been placed under medical observation.

Epidemiological surveys and source tracing work regarding the cases are underway.

Manzhouli launched its first round of citywide nucleic acid testing on Nov. 22, and the second round of tests on Friday.

The autonomous region currently has four imported cases.