A Royal Caribbean International ship returned to port in Singapore on Wednesday after a passenger on the so-called cruise to nowhere recorded a positive coronavirus test.

Other passengers and crew on the Quantum of the Seas who came into close contact with the person have tested negative, the ship's operator said.

The ship departed Singapore on Monday on a four-day round-trip with no port calls. It had close to 1,700 passengers on board, according to the operator.

The Quantum of the Seas, a Royal Caribbean International cruise ship, is docked at the Marina Bay Cruise Centre Singapore, in Singapore, on Dec. 9, 2020. (Kyodo)

The government-run Singapore Tourism Board identified the infected passenger as an 83-year-old male. Even though he had tested negative for the virus prior to the cruise, he developed symptoms and reported to the medical center aboard the ship, it said.

"The ship is returning to Singapore so that passengers can disembark and medical support (can be) provided if necessary," Annie Chang, cruise director at the board, said in a statement.

"Emergency response plans have been activated according to guidelines including immediate isolation of close contacts, contact tracing and deep-cleaning of the ship."

Royal Caribbean launched its cruise to nowhere trips for Singapore residents this month under a government-arranged pilot program for the cruise industry, which has been hard-hit during the pandemic.

The city-state has had just a small number of community transmission infections since around September.

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