In a major city in northeastern China, more than 7,500 people have been quarantined after three new coronavirus cases have been discovered in the past five days as the region has seen an increase in infections.
China has largely brought the virus under control after months of blocking and curbing travel, but fears of a second wave have increased as clusters have formed in the northeastern provinces and downtown Wuhan.
Shenyang, a city of approximately 7.5 million people, reported its first new local case in 89 days on Monday and two more new local cases on Thursday.
The government confirmed on Thursday that the new cases were linked to a cluster in the city of Shulan in the neighboring province of Jilin, nearly 500 kilometers away.
Around 7,500 people who had traveled from Jilin since April 22 and were in close contact with the three local cases in Shenyang had to undergo 21-day quarantine and three nucleic acid tests.
The city has also postponed the reopening of schools, some of which were planned to welcome students back on Friday.
Authorities in the Wuhan pandemic ground zero have also ordered mass COVID-19 tests for all 11 million residents after a new group of cases occurred over the weekend.
President Xi Jinping said Thursday that containment measures in Jilin, near Heilongjiang and Wuhan must be stepped up "to prevent infections from recurring," Xinhua said.
The cities of Jilin and Shulan, both in Jilin Province, were closed last week after a first cluster that appeared in Shulan on Monday passed to Jilin.
Transport was strictly controlled, schools were closed and mass gatherings were banned.
Jilin's deputy mayor warned on Wednesday that the situation was "extremely serious and complicated" and "there is a great risk of further spread".
The Shulan cluster was connected to a local woman whose travel history was not yet known overseas or who had previously been exposed to the virus, which raised concerns about its unknown origin.
(This story was not edited by NDTV staff and is generated automatically from a syndicated feed.)