A large part of China's major economic hub of Shanghai has been put under strict anti-virus restrictions after a lockdown in the eastern half of the city was partially extended.

On Friday, Chinese authorities reported 9,875 community transmissions across the country, including infected people without symptoms.

In Shanghai alone, a record 6,311 new cases were reported.

The two-stage lockdown began in eastern Shanghai on Monday. It was due to end on Friday.

But authorities have decided to extend it in all residential areas in the populous Pudong New Area.

In the western half of Shanghai, where many Japanese expatriates also live, residents have been placed under lockdown from Friday to Tuesday. They are required to undergo PCR testing during the period.

There are concerns about the negative impact the lockdown measures will have on people's lives and economic activities.