People wearing face masks walk along a street of Causeway Bay in Hong Kong, Aug 1, 2020. (LO PING FAI/XINHUA)

HONG KONG - Hong Kong reported three imported COVID-19 cases on Monday, pushing the city’s tally to 11,990.

The new patients included a 55-year-old man who flew in from the Netherlands, a 43-year-old man from the United Arab Emirates and a 36-year-old woman from the United States, according to a statement from the Centre for Health Protection.

They had all been fully vaccinated in Hong Kong before they traveled abroad, the CHP added.

The Centre for Health Protection also said that eight places in Hong Kong were put under mandatory testing orders after they were visited by the two patients with mutant strains

The 55-year-old man, who lived at Harbour Place Tower 6 in Hung Hom, left Hong Kong for Spain on July 11 and tested negative before his departure. He tested positive at the Hong Kong airport upon his return and had the L452R mutant strain.

The 36-year-old woman, who resided at Bohemian House in Sai Ying Pun, left Hong Kong on July 16 for the US. She tested negative for the virus on July 14 before she left. The patient came back to the city on Sunday and tested positive the N501Y mutation.

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Since the two patients spent the majority of their incubation periods overseas, their infections have been classified as imported cases, the CHP said.

The CHP also said that eight places in Hong Kong were put under mandatory testing orders after they were visited by the two patients with mutant strains.

The places visited by the two in mid-July included Harbour Place Tower 6 in Hung Hom, Bohemian House in Sai Ying Pun, Euler Hermes Hong Kong Services Limited at Cityplaza 4 in Quarry Bay, SOZO Hair Design at Worldwide Commercial Building in Central, Nha Trang Vietnamese Cuisinea at On Shing Terrace in Quarry Bay, CrossFit Cavaliers in Shek Tong Tsui, LOCKCHA at Tai Kwun in Central and Chaiwala in Central.

These places have been included in the compulsory testing notice, the CHP said. For prudence's sake, those who have completed a COVID-19 vaccination course are also required to take mandatory tests if they have visited the above premises at a specific time and date, the CHP added.

On Sunday, the health authorities also issued a testing order to Lok Yuen in Kowloon City after a woman who lives there tested positive in the UK.

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The 52-year-old woman departed Hong Kong on July 15 to London via flight CX251. Her specimen collected three days later tested positive for COVID-19 and she remains asymptomatic.

As of Sunday, more than 3.25 million people in Hong Kong have been inoculated with at least the first COVID-19 vaccine shot, accounting for 47.9 percent of people aged 12 and above. Among them, some 2.46 million have been fully vaccinated.