Filipino migrant workers line up at the temporary testing center for COVID-19, in Hong Kong, May 1, 2021. The government ordered foreign domestic helpers to take COVID-19 tests after two helpers were diagnosed with a more infectious strain of the virus. (KIN CHEUNG/AP)

HONG KONG – All residents of a nine-story building in Hong Kong's Tsim Sha Tsui area were evacuated on Monday night to government facilities for 21 days of quarantine after a housewife living there tested positive for the N501Y coronavirus variant.

The 28-year-old woman, who flew to Hong Kong from India on April 4, returned to the Beauty Mansion on Kimberley Road after finishing a three-week quarantine at Regal Oriental Hotel on April 25.

READ MORE: HK helpers ordered to get COVID­-19 tests as concern over variant grows

The government said residents of Beauty Mansion who are already showing will be sent to the hospital for treatment, while a 21-day quarantine at government facilities will be arranged for asymptomatic patients

She tested negative on April 26 and received an “indeterminate” result on Friday, but a third test on Sunday came back positive. She also tested positive for COVID-19 antibodies. Her case was classified as imported.

The government said residents of Beauty Mansion who are already showing will be sent to the hospital for treatment, while a 21-day quarantine at government facilities will be arranged for asymptomatic patients.

The woman was the city’s sixth COVID-19 variant carrier who has entered the community.

On Thursday night, about 1,000 people at a residential building in Tung Chung were evacuated as a domestic helper there and a baby she attends to were found with the variants.

ALSO READ: HK govt refutes 'misleading' report on COVID-19 measures

The Centre for Health Protection said in a statement that the 39-year-old helper in Tung Chung was found to have visited the Citygate Outlets shopping center on April 11, the same day when two other patients of variants visited the same mall.

The duo, a 29-year-old man flying from Dubai, and a female friend he lived with at a flat in Jordan, were the city’s first mutation cases. They had also visited Curry Lounge, a restaurant at SeaView Crescent in Tung Chung, on the same day.

Researchers revealed on Saturday that the helper has the same genome sequence with the 29-year-old man’s.

The government has issued a compulsory testing notice to all people who had been present at the two premises on April 11.