Millions of people across China have been plunged into a lockdown on Sunday as cases of Covid-19 tripled after a surge in infections in the north east cause the worst outbreak the country has seen in two years. 

A total of 1,938 new cases of coronavirus have been reported by authorities in China on Sunday, which is three times the Saturday figures. 

Tighter controls have been put in place for those looking to access Shanghai, with services in the eastern port city, of over 24 million people, have been suspended after their cases rose by 15 to 432.

Anyone wanting to enter Shanghai requires a Covid-19 test to enter.  

The nationwide surge in cases has seen authorities close schools in Shanghai and lock down central neighbourhoods in the southern city of Shenzhen. 

Neighbouring mainland cities Jilin and Changchun, in the north east, contributed to around three quarters of the total, reporting 1,412 total cases.

Entry to Changchun, which neighbours Jilin city and is within the Chinese province of Jilin, has been suspended, with families also told to stay at home.  

The infection numbers are low in comparison to various other countries which are co-existing with Covid, such as the UK, but authorities are enforcing a 'zero-Covid' policy which aims to find and quarantine every infected person in China.

Anxiety has mounted over the resilience of the country's zero tolerance approach in the face of this outbreak. 

Another 18 provinces in northeastern cities are battling clusters of the Omicron and Delta variants.