A British woman has gone missing from a cruise ship while it was crossing the Atlantic, travel operator Tui has said.

The 72-year-old was last seen aboard Tui’s Marella Voyager on Monday while the vessel was en route to the Caribbean. The ship could have travelled hundreds of miles in the time between when she was last seen to when she was reported missing.

Staff realised the passenger was missing on Tuesday, when they noticed her bed had not been slept in. The alarm was raised and a search carried out, Tui said in a statement.

It is understood the missing guest was then reported to the US Coast Guard, which asked the ship to continue to its crossing rather than reverse course and search for the woman.

Holidaymakers were told to abandon dinners, drinks and entertainment as the crew carried out an emergency headcount on Tuesday evening, the Daily Mail reports.

Passengers stood in lines of four while staff scanned boarding cards to verify the identity of every person on the ship, according to the newspaper.

The USCG Rescue Co-ordination Centre in Norfolk, Virginia has issued an alert calling on any ships nearby to “keep a sharp look out” for the woman, the Mail reports. The BBC has contacted the USCG for comment.

The Marella Voyager, carrying around 2,000 passengers and 800 crew, left Malaga on 4 November and is due to arrive in Antigua on Friday before calling at Dominica and finishing its voyage in Barbados on Sunday.

A spokeswoman for Marella Cruises said it was “deeply saddened” by the disappearance, adding: “Our thoughts are with the guest’s loved ones at this very difficult time.

“We’re supporting the authorities with their enquiries, and out of respect for the guest and their family, we won’t be commenting further at this stage.”

A UK Foreign Office spokesperson said: “We are supporting the family of a British national reported missing on a cruise ship in the Atlantic Ocean and we are in touch with the relevant authorities.”

In a separate case, a cruise ship pianist was found treading water on Sunday around 20 miles off the Californian coast after falling overboard.

Two fishermen discovered the Royal Caribbean employee near Catalina Island and officials believe he may have been in the Pacific Ocean for nine hours, according to CBS News, the BBC’s US news partner.