The Line 6 subway in Shenzhen, South China's Guangdong Province, began trial operations on Tuesday, along with line 10. Formal service is scheduled for August. Photo: CNSphoto

South China's Guangdong Province has raised the COVID-19 risk alert levels from low to medium in four areas after the detection of new imported cases increased and work resumption intensified the flow of people.

The Health Commission of Guangdong Province announced the list of epidemic risk levels late on Sunday for areas under its administration. The province was the first to raise risk levels since the outbreak was basically brought under control in China.

The risk levels of Yuexiu district and Baiyun district in Guangzhou, Bao'an district in Shenzhen and Huilai county in Jieyang have been adjusted from low to medium. 

Other areas in the province remain at low risk and no areas are at high risk. The authority didn't explain the moves.

Seven more imported cases were confirmed in Guangdong on Sunday, bringing the total to 172, data showed.

The new imported cases from Canada, the UK, the US, Cambodia and the Niger entered Guangdong via the Guangzhou Baiyun International Airport in Baiyun district.

Guangzhou reported five local cases who had been infected by the imported cases as of press time, of whom four live in Yuexiu district.

Besides, the Shenzhen Bao'an International Airport has received up to 70 passengers from abroad each day recently, media reported.

The airport said on Chinese Twitter-like Sina Weibo on Sunday that it planned to operate 652 flights on that day and its flight volume has gradually increased.

On Saturday, Huilai county in Jieyang reported two local cases that were infected by imported cases.

Residents in Guangdong reached by the Global Times on Monday expressed their support for the new move, and they said that they considered such an adjustment to be timely.

A resident in Huilai, who requested anonymity, told the Global Times that he was worried if more cases would occur in the county, where medical resources are poor and many of the local residents are elderly people and children. He noted the county recorded no infection before the two cases, as the local government had tried its best to prevent and control the epidemic.

A resident surnamed Han in Guangzhou said the flow of people is intensifying in Yuexiu and Baiyun districts, especially as work resumption begins. "Yuexiu has many people from areas outside the province and from abroad, which sometimes makes management chaotic," said Han.

A Nigerian man who was tested positive for COVID-19 refused to undergo medical quarantine and assaulted a nurse, beating her and biting her face on April 1, which caused a great uproar and concern over public safety on China's internet.

Many netizens who claimed to be residents in Guangdong called on the government to follow Beijing's lead and conduct centralized quarantine for all passengers returning from abroad.