Miami (CNN) -- A Canadian woman was nowhere to be found when her cruise ship docked in Florida, prompting an FBI investigation and a Coast Guard search Thursday between Palm Beach and the Bahamas, authorities said.
A man, also Canadian, told a Celebration Cruise Line staff member around 8 a.m. on Wednesday -- as travelers were disembarking in Palm Beach -- that he hadn't seen his female traveling companion for seven hours, Celebration spokesman Glenn Ryerson told CNN.
That disclosure prompted an extensive search of the ship, after which police were notified, according to the cruise line's spokesman.
The couple -- who Ryerson said were not married but were "certainly" friends -- had left Palm Beach on Saturday destined for the Bahamas. They disembarked in the Caribbean nation the next day, spending two nights there through a package offered via the cruise line, Ryerson said.
"We believe she did reboard" on Tuesday for her return trip to Florida, the spokesman said.
After the search, the ship set sail again at 6 p.m. Wednesday on another scheduled trip, Ryerson said.
By then, authorities had begun their probe into the woman's disappearance.
"The FBI is investigating, and we have launched a search-and-rescue operation," said Coast Guard spokesman Nick Ameen.
Specifically, two Coast Guard cutter ships -- the Drummond and Kingfisher -- are canvassing the waters off Florida's southeast coast, Ameen said.
They are getting air support in the form of crews aboard a C-130 Hercules plane and an H-60 Jayhawk helicopter out of the Coast Guard's Clearwater air station, as well as from a Florida National Guard airplane crew, Ameen said.
Chris Plunkett, a spokesman for the Canadian Embassy in Washington, said Thursday that foreign ministry officials were aware of the missing woman.
Canadian consular officials are working with the cruise line and Florida authorities and are preparing, as needed, to provide assistance, Plunkett said.
CNN's Carol Cratty contributed to this report.