HONG KONG -- Hong Kong's Center for Health Protection (CHP) reported nine new imported cases of COVID-19 on Sunday, taking the total tally to 12,461.

The newly reported cases all involved mutant strains. A total of 53 cases have been reported in the past 14 days and all were imported, according to the CHP.

In view of the recent global developments related to the Omicron COVID-19 variant, the Hong Kong Special Administrative Region (HKSAR) government announced on Thursday that boarding and quarantine requirements for inbound travelers from Finland, Ghana, South Korea, Norway and Saudi Arabia will be tightened from midnight on Dec. 5, while all transit passengers from overseas places and China's Taiwan will be required to present negative nucleic acid test results when boarding a flight for Hong Kong from midnight on Dec. 8.

Since the launch of the government inoculation program in late February, over 4.77 million people, or 70.9 percent of the eligible population, have taken at least one shot of the COVID-19 vaccine, while over 4.54 million, or 67.6 percent, are fully vaccinated.

Meanwhile, a total of 199,542 people have taken the booster shot in Hong Kong as of 7:00 pm local time Saturday.

The HKSAR government expects the third-dose vaccination to cover 1.86 million people.