China’s worst coronavirus epidemic since the outbreak of the pandemic one year ago escalated Wednesday, with many more cases across the country, the closing of one city and the punishment for its leaders.

China’s population has been virtually unaffected by the virus since last year’s initial outbreak. There have been strict border controls, local distancing, and quarantine measures to stop any flare-ups.

The country is now on high alert due to an outbreak of cases linked to the international airport in Nanjing’s eastern city. China reported 71 cases of COVID-19 local transmission Wednesday. More than half of these were in coastal Jiangsu, the capital.

Wuhan was the city in the center where the first COVID-19 cases were discovered. Mass testing revealed that some of the newly reported cases are very similar to those found in Jiangsu. These cases were caused by the highly transmissible Delta variant, which was first identified in India.

Another COVID-19 hotspot emerged in Zhangjiajie. It is located near the scenic area of Zhangjiajie that is famous for its sandstone cliffs and caves, forests, waterfalls, and forests.

Sunday was the day that the city sealed residential areas to prevent people from leaving their homes. Officials issued a second order Tuesday saying that no resident or tourist could leave the city.

On Wednesday, the Communist Party disciplinary committee of the city government issued a list of officials in localities who had “a negative effect” on pandemic prevention or control work.

Since last week, the city has only seen 19 cases. Three of these were people without symptoms. These are separately counted. According to the Shanghai government-owned newspaper, the Paper, the individual cases of Zhangjiajie’s disease have reached at least five other provinces.

Yangzhou, located next to Nanjing, saw far more cases than the rest. As of Tuesday, it had 126 cases.

Officials from the National Immigration Administration repeated the message on Wednesday, after announcing that they would suspend the issuance of passports to travelers with an urgent need last week.

China had given 1.71 billion doses of vaccines to its population of over 1.4 billion as of Tuesday. Although it is not known how many are the first or both doses of vaccines, at least 40% of the population has been fully protected according to earlier announcements.

Although officials claim that the vaccines protect against severe illness and hospitalization, Chinese companies have not made public any data about the effectiveness of their vaccines against the delta variant.

Out of the 71 local cases, 25 international travelers have COVID-19, and they have been quarantined. This brings the total number of cases to 96 for Wednesday. According to the National Health Commission, 15 people were tested positive for the virus and have not yet developed symptoms.

China reported 4,636 deaths, 93,289 COVID-19 cases, and most of these were from the initial outbreak in Wuhan, which peaked early last Year.