* Coronavirus outbreak in Beijing rises to 106 cases over 5 days
* Authorities impose curbs on travel from Chinese capital
* Neighbourhood restrictions, checks ramped up (Adds increase in number of "medium-risk" neighbourhoods to 27)
By Lusha Zhang and Ryan Woo
BEIJING, June 16 (Reuters) - 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.
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 Tuesday, Beijing had designated 27 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, citing municipal officials.
All outbound taxi and car-hailing services have been suspended. Some long-distance bus routes between Beijing and nearby Hebei and Shandong provinces were halted.
At least three shuttle bus services from Hebei and another from Inner Mongolia to Beijing's Capital Airport, a major regional transit hub, were suspended. Bus services from Hebei to Daxing, Beijing's other major airport, were reduced.
Some long-distance bus services from Beijing to surrounding Hebei were also halted. Highways out of the capital remained open.
Concerned about contagion risks, many provinces have imposed quarantine requirements on visitors from Beijing. In the last three days, Hebei, Liaoning and Sichuan have reported new cases linked to the Beijing wholesale centre.
On Tuesday, Shanghai started to require travellers from medium-to-high risk COVID-19 areas in China to be quarantined for 14 days.
"I'm so worried for Shanghai - just look at the new cases in Beijing," said Wang Jiahe, 22, a university student. "There is so much daily air and road traffic (between the cities)."
The stakes are high for Shanghai, which has been invited to host two Formula One races this season. U.S. airlines are also poised to resumes flights to the city.
While not in a Wuhan-style lockdown, Beijing has gone into a "wartime" mode on a district level, with neighbourhoods instituting 24-hour security checkpoints, closing schools and banning wedding banquets.
Some parts of Beijing including the city's old-style hutong neighbourhoods were fenced up, with some imposing single entry points.
"My neighbourhood has four or five entry ways, and when the controls came, only the southern entrance was open, and we now need to show our entry cards and have our temperatures taken," said a man surnamed Zhao who lives in the northeast of Beijing.
"It's a big neighbourhood with lots of office workers, so it is extremely inconvenient for a lot of people."
However, in Huaxiang, the only high-risk neighbourhood, some residents demanded officials impose more stringent contact tracing protocols.
Officials were relying on people to identify themselves as having visited Xinfadi, 9 km away, residents said.
"How can you hope for people to be honest enough to voluntarily report their links with Xinfadi?" said a male Huaxiang resident surnamed Yuan.
"Since we're in a 'wartime' mode, the local authorities should test everyone."
Hundreds of workers in the catering sector queued to be tested at a site in central Beijing on Tuesday, many of them having waited for more than an hour in the summer heat.
"I can't guarantee that I don't have the disease," said Zhang Qi, a restaurant worker. (Reporting by Ryan Woo, Liangping Gao, Tina Qiao, Lusha Zhang Se Young Lee and Huizhong Wu in Beijing; Winni Zhou in Shanghai; Additional reporting by Beijing and Shanghai newsrooms; Editing by Lincoln Feast, Jane Wardell and Nick Macfie.)
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