BEIJING — A major city in central China that’s seen a flare-up of Covid-19 cases locked down on Thursday, with local authorities using language similar to that used during the height of the pandemic in the country.

The outbreak in Xi’an city — population 13 million — stems from the delta variant, authorities said. Mainland China only has a few Omicron cases, but the strain is rapidly spreading. become the dominant variant in the U.S.

The number of confirmed cases for coronavirus in Xi’an is much lower than other international cities. The city reported an unspecified amount of hemorhagic virus cases. It is a disease with high mortality that can be transmitted via rodents. The authorities in the area have reported this. disease appears seasonally, typically from October to January, and from April to June.

Residents were told by the Xi’an municipal governments not to leave their home on Wednesday. They also instructed apartment buildings and work places to obtain passes for entry and exit starting Thursday.

Authorities said that each household cannot send out one person every two days for groceries or other essentials. This is in line with some of the stricter policies in place in various parts of the country as of early 2020.

Xi’an told movie theatres and other in-person education institutions that they would have to stop operations. It also prohibited restaurants from serving food. Schools have largely shut down or relocated classes online, while authorities ban large-scale events.

Between Dec. 9th and Tuesday, the city had reported 143 locally transmitted cases. Late Wednesday, authorities announced that the second round of testing across the city found 127 cases. The figures did not appear to be identical.

Official data accessed by Wind Information shows that Xi’an contributes just 1% to China’s GDP. American chipmaker and electronic giant Samsung Micron have major operations in the city, which is home to many research or manufacturing centersHigh-tech Industries, including aerospace, semiconductors and others.

The city also attracts many tourists for its Terracotta Warriors — an army of clay sculptures from ancient times. Xi’an, located in central China about 800 miles away from Shanghai’s east coast metropolis, is the city’s last major urban area before the western poorer areas.

Because of the spread of coronavirus in China, Xi’an has one high-risk area and 40 medium risk areas. These risks affect how virus control is implemented, particularly when determining whether traveler can be allowed in another city.

A wider outbreak started to subdue in southeast China. As of Tuesday, authorities said the city of Hangzhou — home to Alibaba’s headquarters — resumed low-risk status, after reducing the risk level of the last of medium risk areas in the city.

According to authorities, Hangzhou and Zhejiang’s two remaining parts reported 486 confirmed cases in the period Dec. 5- Tuesday afternoon. According to the National Health Commission, one case of locally-transmitted disease was reported in the province on Wednesday.

Chinese authorities remain on guard for any outbreaks. This is particularly important given that millions of Chinese people will travel to their homes for Lunar New Year. It officially begins on January 31. The authorities are particularly concerned about the safety of 2022 Winter Olympics, set for Beijing on February 4.

Disclosure: NBC Sports is owned by NBCUniversal, a parent company of CNBC. NBC Olympics holds the U.S. broadcasting rights to all Summer Games and Winter Games up to 2032.