HONG KONG - Hong Kong authorities prevented a Royal Caribbean cruise ship from departing the city's terminal late on Thursday as a crew member was found to have COVID-19 after routine testing, the government and the cruise operator said.

The Spectrum of the Seas ship was scheduled to begin a "cruise to nowhere" journey in nearby waters, restricted to half capacity and only for fully vaccinated residents who tested negative for the virus 48 hours prior to the trip.

About 1,000 passengers out of a total of 1,200 had already boarded the ship before the four-night trip was canceled. All have to undergo compulsory testing but were allowed to leave the ship as they did not have direct contact with the crew member

About 1,000 passengers out of a total of 1,200 had already boarded the ship before the four-night trip was canceled. All have to undergo compulsory testing but were allowed to leave the ship as they did not have direct contact with the crew member.

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The 40-year-old crew member tested positive for COVID-19 in Malaysia in July and then tested negative for more than 10 times since returning to Hong Kong in August. He was fully vaccinated with the mainland-made Sinovac vaccine.

His latest sample was collected on Oct 19 and had a "very low viral load", the Centre for Health Protection said in a statement, adding he was asymptomatic.

"Based on the epidemiological and laboratory findings, the case is compatible with a re-positive case," the CHP added.

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The CHP said it has requested the cruise to suspend its journey for 21 days for prudent sake. "They can receive guests starting from November 11," it added.

Hong Kong has some of the most stringent travel restrictions in the world and is virtually COVID-19 free. The financial hub reported two new imported cases on Friday, bringing the overall tally to 12,314.

Both cases involved a L452R mutant strain, the CHP said in a separate statement.

One of them — a 43-year-old foreign domestic helpter — arrived in Hong Kong on Oct 18 from the Philippines, which had been designated as a "high-risk" place by the Hong Kong government. She has tested positive at the designated quarantine facility at Penny's Bay.

Another case involved a 31-year-old woman who had flown in from the Maldives on Qatar Airways flight QR818 via Doha. She is a close contact of an imported case confirmed previously, the CHP said.

Both new patients had been fully vaccinated against COVID-19, the CHP added.

With inputs from Agencies