The situation in China's capital Beijing turned grim after clusters of COVID- 19, while the country's financial hub Shanghai reported 39 more deaths due to the virus, the highest in a day during the current outbreak since last month.
On Saturday, the Chinese mainland reported 21,796 cases, including 1,566 positive cases and the rest asymptomatic cases mostly in Shanghai, China's National Health Commission reported on Sunday.
The city, which had 22 new community cases recorded on Saturday, went on high COVID 19 alert as the city braced to test some sections of the population.
The city went on high alert after 10 middle school students tested positive for COVID- 19 on Friday, following which city officials suspended classes in the school for a week.
The deputy director of the Beijing Centre for Disease Prevention and Control, Pang Xinghuo, said undetected local transmissions started in the city about a week ago, and involved schools, tour groups and families.
Pang was quoted by the Hong Kong-based South China Morning Post as saying that there were hidden transmissions for a week and the infected people came from different backgrounds and a wide range of activities.
Mass testing will be conducted on senior citizens who had been on tour groups, construction workers and the people working at the school where the cluster was identified, Pang said.
On Friday, Beijing Communist Party boss Cai Qi, Mayor Chen Jining and other city leaders met twice to organise control efforts.
The meeting pointed out that our city of Beijing had suddenly recorded some cases and many transmission chains were involved. The risk of further hidden transmission is high. The situation is urgent and grim, according to the state-owned Beijing Daily.
Shanghai was the epicenter of the Omicron variant of the virus.
The report said that 16 other provincial-level regions on the mainland saw new local COVID 19 cases, including 60 in Jilin, 26 in Heilongjiang and 22 in Beijing.
The report said 29,531 people were undergoing treatment for the coronaviruses across the country.
On Saturday, Shanghai reported 23,370 new cases, taking the city's total to 466,000 since March 1.
The death toll in the city of 87 so far in the city since the emergence of the Omicron virus has resulted in 39 deaths from COVID- 19, according to the city of 26 million people on Saturday.
The death toll due to coronaviruses in China rose to 4,725, increasing the death toll in the country since it first emerged in Wuhan in December 2019.