Some 2,300 people were allowed to depart a cruise ship in Greece just one day after officials revealed that an Austrian tourist who had already disembarked had tested positive for the coronavirus, according to reports.

The 1,579 passengers and 723 crew members were ordered back on board the MSC Opera in Athens “immediately” Wednesday as the group enjoyed an excursion on the mainland, the Daily Mail reported.

Passenger Antonio Montalto told the outlet that no one explained the order at first — and some passengers assumed it had to do with the tensions on the Greece-Turkey border.

But the captain later explained that an Austrian tourist who left the ship the Friday before, on Feb. 28, came down with the virus. It is unclear where he contracted the illness but he had traveled on the ship for 11 nights from February 17, embarking and disembarking in Genoa in northern Italy — a region highly affected by the deadly bug, according to The Telegraph.

He reportedly began showing symptoms after he left the cruise and was diagnosed back in Austria on March 3.

“The check was to assess if any additional onboard health measures should be put in place following reports that a passenger who had disembarked the ship six days ago had tested positive for COVID-19 coronavirus two days after returning to Austria via Northern Italy,” an MSC spokesman said in a statement to the Daily Mail.

The spokesperson also added passengers were never “quarantined and all were able to freely make use of the ship’s facilities and restaurants before it departed yesterday.”

Around 1 p.m. local time Thursday, the vessel was given the all-clear from Greek health authorities to continue its journey from Piraeus to Corfu, Metro UK reported.

Once in Corfu, all on board were allowed to leave the vessel.

Health authorities “deemed the vessel needed no further health measures beyond the ship’s existing strict preventative health measures,” the spokesman said in the statement to the Daily Mail. “There is no reported illness today, nor yesterday, among any of the 2,302 passengers and crew.”

Meanwhile, in the US, dozens of people on board the Grand Princess cruise left in limbo off the California coast will be tested for coronavirus, the cruise liner confirmed in a Thursday morning statement.

The Grand Princess was traveling to Ensenada, Mexico, but instead headed Wednesday to San Francisco following news that a 71-year-old passenger died from the virus after returning home, the company said.

Last month, the Diamond Princess cruise ship — with more than 700 infected passengers — was quarantined in Japan.