The government on Monday evening imposed lockdowns on two blocks of a public housing estate in Sham Shui Po, after sewage discharged from the buildings tested positive for Covid.
Residents of Cheong Him House and Cheong Yat House at Nam Cheong Estate are required to stay home and undergo tests.
Authorities said they suspect there are infected people in the blocks who don’t have symptoms of the virus.
The officials said they aim to finish the testing operations at 1pm on Tuesday, but they may be extended depending on the test results.
Anyone else who stayed in the blocks for more than two hours between February 8 and February 21 must also get tested by Wednesday.