The Chinese capital banned high-risk people from leaving and curbed public transport on Tuesday to stop the spread of the most serious coronavirus flare-up since February, which has stoked fears of a second wave of infections.

The financial hub of Shanghai demanded some travellers from Beijing be quarantined for two weeks, as 27 new Covid-19 cases took the capital’s current outbreak to 106 since Thursday.

The coronavirus was first identified in December at a seafood market in Wuhan, capital of the central Chinese province of Hubei, and has since spread around the world, infecting more than 8 million people and killing more than 436,000.

The new outbreak in Beijing has been traced to the sprawling Xinfadi wholesale food centre in the southwest of Beijing where thousands of tonnes of vegetables, fruit and meat change hands each day.

As of Monday, Beijing had designated 22 neighbourhoods as medium-risk areas, requiring them to subject people entering to temperature checks and registration.

So-called high-risk groups in Beijing, including people who are close contacts of confirmed cases, are not allowed to leave the city, state media reported.