In this July 27, 2020 photo, a medical worker takes a swab sample from a resident at a COVID-19 test site in Dalian, northeast China's Liaoning province. (LONG LEI / XINHUA)

BEIJING - The port city of Dalian in northeast China's Liaoning province on Monday tightened up COVID-19 prevention and control measures in five urban communities, after two locally transmitted cases were discovered.

The province's health commission on Monday said one confirmed case and one asymptomatic case were reported Sunday in Dalian.

Dalian has registered several locally transmitted infections since Dec 15, when four port workers handling cold-chain products were detected as asymptomatic carriers

The confirmed case was previously a asymptomatic case that was first reported on Dec 17, while the newly logged asymptomatic case was detected during nucleic acid screenings in the monitored area.

Dalian has registered several locally transmitted infections since Dec 15, when four port workers handling cold-chain products were detected as asymptomatic carriers.

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The municipal COVID-19 prevention and control headquarters issued a notice on Monday that five communities in Jinpu New District of Dalian initiated reinforced epidemic control measures, urging all residents to stay home. The residents are allowed to buy daily necessities in restricted areas. All public facilities including schools and kindergartens in the area are closed. 

23 new cases on mainland

Earlier on Monday, the National Health Commission said that it received reports of 23 newly confirmed COVID-19 cases on the Chinese mainland Sunday, including 21 imported ones and two locally transmitted ones.

The two local cases were reported in Liaoning and Heilongjiang, respectively, the commission said in its daily report.

Of the 21 new imported cases, eight were reported in Shanghai, six in Inner Mongolia, three in Guangdong, two in Fujian and one each in Shanxi and Sichuan, the National Health Commission said

Of the new imported cases, eight were reported in Shanghai, six in Inner Mongolia, three in Guangdong, two in Fujian and one each in Shanxi and Sichuan, the commission said.

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No additional deaths related to the disease were reported, it added.

Another 14 patients were discharged from hospitals after recovery, the commission said, adding that there were 318 patients still receiving treatment.

By the end of Sunday, a total of 4,136 imported cases had been reported on the mainland. Among them, 3,859 had been discharged from hospitals following recovery, and 277 remained hospitalized. No deaths had been reported among the imported cases.

The total number of confirmed COVID-19 cases on the mainland reached 86,852 by Sunday, including 81,900 recoveries and 4,634 deaths, according to the commission.

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As of Sunday, there were seven suspected COVID-19 cases on the mainland, and 6,927 close contacts remained under medical observation.

Sunday also saw 15 newly reported asymptomatic cases on the mainland. On the same day, one asymptomatic case was re-categorized as a confirmed one.

A total of 208 asymptomatic cases were under medical observation, out of which 182 were imported cases, the commission said.

By the end of Sunday, 8,152 confirmed cases, including 130 deaths, had been reported in Hong Kong Special Administrative Region (SAR), while 46 confirmed cases had been reported in Macao SAR, and 766 cases, including seven deaths, in Taiwan.

Altogether, 6,837 patients in Hong Kong SAR, 46 in Macao SAR and 627 in Taiwan had been discharged from hospitals.

Taiwan, which also has a 14-day quarantine, said on Sunday there were no plans at present to stop flights from Britain.

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