BEIJING (REUTERS, BLOOMBERG) - Mainland China reported 16 new Covid-19 cases as of the end of Saturday (July 18), up from 22 reported a day earlier, the Chinese national health authority said on Sunday.

Of the new cases, all 13 of the locally-transmitted cases were found in Urumqi, the capital of China's far western region of Xinjiang.

The other three were imported infections involving travellers from overseas, according to the National Health Commission (NHC) and Xinjiang local health commission.

The NHC reported one new imported asymptomatic case in Shanghai, and Xinjiang's local health authority reported 18 new asymptomatic patients in Urumqi.

The far west city went into "wartime mode" on Saturday, launching an emergency response plan after the city reported 16 new coronavirus cases in the previous day.

The city of more than 3.5 million people has 30 confirmed cases and 41 asymptomatic carriers since it reported its first infection in five months on July 15.

Residents have been banned from leaving their housing compounds, with provisions made for those who are sick or in special situations, local media reported on Friday.

People arriving from other provinces will be quarantined for seven days.

The local government in Urumqi, the capital of Xinjiang province, said on Saturday that it is offering free coronavirus tests.

They will be done in two phases: people in residential areas who've had direct or indirect contact with those who are confirmed or suspected to be infected will be tested first while residents in other housing compounds, and government and civil servant institutions will be tested in the second phase.

As of Saturday, mainland China had 83,660 confirmed coronavirus cases, the national health authority said. The death toll remained at 4,634.