Pedestrians walk past a residential building complex in Hong Kong on May 28, 2021. (ANTHONY WALLACE / AFP)

HONG KONG - The Hong Kong government on Thursday night cordoned off a building in Sha Tin after a COVID-19 mutant case was detected in the area.

A restricted area was set up at Golden Glory Court, Phase 1, Golden Lion Garden, 5-7 Chui Tin Street, in Sha Tin at 7 pm after a 41-year-old resident tested preliminarily positive for L452R mutant strain and the source of his infection could not be traced.

As of 1 am Friday, some 400 people have been tested. Results all came out negative.

The Centre for Health Protection said the 48-year-old male patient is a cargo handler at Hong Kong International Airport and undergoes COVID-19 testing weekly

The Centre for Health Protection said the 48-year-old male patient is a cargo handler at Hong Kong International Airport and undergoes COVID-19 testing weekly.

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He tested negative on September 29, but the result of his sample submitted on October 6 came back preliminarily positive.

The CHP added that he had no recent travel history and mainly performed duties at SuperTerminal 1. He last went to work on October 7.

The patient, who showed no symptoms of the virus, received two doses of the Sinovac vaccine in Hong Kong on June 25 and July 28, the CHP said.

It added that the patient’s workplace and the places he had visited during the incubation period will be included in a compulsory testing notice.

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The CHP also reminded those who had been present at the building in Sha Tin for more than two hours from September 15 to October 7, even if they were not present in the restricted area at the time of the targeted testing operation, must undergo compulsory testing on or before October 9.