BEIJING: China's capital reported 22 new cases of the coronavirus on Sunday after a mass testing effort that has collected more than two million samples in a race to contain a new outbreak.

The fresh cluster in Beijing has raised fears of a resurgence of the virus in China, which had largely brought the disease under control over recent months.

Dozens of communities have been sealed off in the city to contain the spread, with residents told to avoid non-essential travel and schools closed.

The new infections reported Sunday include a nurse - the first health worker to test positive since the re-emergence of the illness just over a week ago.

More than 220 people have tested positive in the new cluster.

State news agency Xinhua said local authorities had set up more than 2,000 sites across the city that had obtained 2.3 million samples.

The latest outbreak first emerged at a wholesale food market, prompting fears over the safety of the city's food supply.

The virus was detected on chopping boards used to handle imported salmon. Beijing officials on Friday advised citizens to dispose of frozen seafood and bean products bought from the site.

The Xinfadi market supplies more than 70 percent of Beijing's fresh produce and has been closed.