(CNN) -- Rescue crews scoured the waters off Australia's eastern coast Friday for two cruise ship passengers who are believed to have fallen overboard.
The 30-year-old man and 27-year-old woman were reported missing when the Carnival Cruise ship Spirit docked in Sydney on Thursday morning, CNN affiliate Seven Network reported. The first clue came when they didn't claim their luggage.
Maritime officers reviewed surveillance video from the ship and determined that Paul Rossington and Kristen Schroder went overboard Wednesday night.
Authorities believe the couple fell about 150 kilometers (93 miles) off Foster, New South Wales.
"We believe that they were up mid-deck, which is halfway up the side of the ship, which is quite a way to fall," said Detective Superintendent Mark Hutchings of the New South Wales Police Marine Area Command.
The couple was sharing a cabin and traveling with family and friends on a 10-day Pacific Island cruise.
Carnival has been plagued by a series of high-profile incidents recently.
In February, an engine room fire left the Carnival Triumph adrift in the Gulf of Mexico, with passengers reporting overflowing toilets and human waste running down the walls in some parts of the ship.
On a March cruise, the Carnival Dream lost power, and some toilets stopped working.
CNN's Tina Burnside and Ric Ward contributed to this report.