Staff members of the Housing Department check whether a person in the "restricted area" at Mei King House, Mei Tin Estate, Sha Tin has undergone compulsory testing, Hong Kong, Feb 8, 2020. (PHOTO/HKSAR GOVERNMENT)

HONG KONG – The Hong Kong government announced on Tuesday to extend a lockdown imposed on a public housing block in Sham Shui Po district for one day after 22 preliminary positive COVID-19 cases were detected overnight.

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The government set up a “restricted area” at Fu Yuet House of Fu Cheong Estate at 7 pm Monday after the coronavirus was detected in sewage discharged from the building. It aimed to complete the exercise by 10 am Tuesday but decided to extend the operation after 22 residents tested preliminary positive in overnight testing.

The government aims to finish the extended operation by 10 am Wednesday

In a statement, the government said the situation there is "worrying" as the test results suggested an “extremely high risk of transmission” in the block.

The extension means residents in the area cannot leave their building for another day and are required to undergo another COVID-19 test for the second day in a row.

The government aims to finish the extended operation by 10 am Wednesday.

Meanwhile, residents of a Sha Tin public housing building were free to leave their houses after an extended lockdown was lifted Tuesday morning. 

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Mei Chi House of Mei Tin Estate in Sha Tin has been put under the "restriction-testing declaration" from around 8:30 pm Sunday. 

As of 12 am Tuesday, a total of about 4,000 person-time has undergone the first round and second round testing, the government said. Fifteen preliminary positive cases were found and the Centre for Health Protection of the Department of Health will take follow-up action, it added.