Residents get tested for COVID-19 in a restricted area at Shek Kip Mei Estate, Sham Shui Po, Hong Kong, Feb 19, 2022. (PHOTO/HKSAR GOVERNMENT)

HONG KONG - Hong Kong health authorities have detected 87 prelimiarny positive COVID-19 cases at a Sham Shui Po building in a two-day lockdown. 

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The government set up a "restricted area" at Mei Wui House of Shek Kip Mei Estate on Thursday evening after a resident tested preliminarily positive to a mutant strain and traces of the coronavirus were found in the sewage discharged from the block.

During the operation, the government assigned staff to visit about 760 households, 79 of them did not answer the door

Residents were required to undergo one COVID-19 test each on Thursday and Friday night. A total of around 3,350 person-time had undergone testing over the past two days and a total of 87 preliminary positive cases were found, the government said in a statement Saturday. 

The results of 10 other cases were indeterminate and the Centre for Health Protection of the Department of Health will take follow-up action.

The targeted testing exercise was completed at around 10 am Saturday and the lockdown was lifted.

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During the operation, the government assigned staff to visit about 760 households, 79 of them did not answer the door. 

The government reiterated that enforcement actions will be taken seriously. Anyone in the "restricted area" who fails to present an SMS notification with a test result as proof of having undergone testing breaches the compulsory testing notice and may be liable to a fine of HK$10,000, it added.