Yunnan Province reported six confirmed and 23 asymptomatic COVID-19 cases on Wednesday, all in Ruili City, said local health authorities on Thursday.
The authorities in the city, which borders Myanmar, announced the strict measures to control the spread of the virus. They spoke at a news conference on Wednesday.
As of 8 am on Wednesday, 317 people who had close contact with the patients had been placed under quarantine for observation. In addition, an expert team sent by the National Health Commission arrived in Ruili on Wednesday to guide the city's epidemic control and prevention work.
Yang Mou, the city's vice-mayor, said at the news conference that residents are required to stay at home. He explained that while the quarantine is initially set to last for one week, the precise time it ends will depend on the results of the citywide testing program.
While they are required to stay at home, families in the city can designate one member to go out to buy daily necessities.
All places of business, apart from supermarkets, pharmacies and markets for agricultural produce, will be closed during the lockdown.
Controls have also been introduced at the city limits to prevent traffic from leaving or entering Ruili, said Gong Yunzun, the city's Party secretary.
"People who must leave the city are required to present a negative coronavirus test taken within 72 hours. People entering the city will be asked to turn back," Gong said at the news conference.