An American woman has vanished from a cruise ship that made several Maritime stops last week.

Police say 71-year-old Sarah Tessier Powell was last seen on board the Holland America cruise ship, Veendam, on Sept. 30 after it left Quebec City.

The ship originated in Boston and made stops in Charlottetown on Oct. 2, Sydney on Oct. 3 and Halifax on Oct. 4.

Powell is travelling alone and police believe she may have slipped past security check points and gotten off in either Charlottetown or Sydney.

They have no idea when exactly she left the ship or where she is now.

Staff on board the ship noticed Powell was missing Oct. 4 just before the boat docked in Halifax.  

“There were some items on board the ship in her cabin, but there were some items missing, leaving us to believe she left on her own accord with no intention of coming back to the ship,” says Const. Pierre Bourdages.

“We do not believe she would have fallen off the ship or met with foul play on the ship.”

While Powell is believed to have left the ship of her own accord, police are concerned for her well-being because she requires medication and may become agitated without it.

Neighbours in Powell’s hometown of Baton Rouge, Louisiana say this isn’t the first time she has gone missing.

“When I first moved to the neighbourhood she came to the door and brought me some flowers and welcomed me to the neighbourhood,” her neighbour, Kelli Spring, tells CTV News. “She said she wasn’t social, but I thought she was sweet and nice.”

Security experts say it’s rare that a passenger would slip past a checkpoint.

Cruise ship passengers in Halifax said they generally feel safe when travelling from port to port.

“Every time we go on or off the ship they know where everyone is,” says passenger Janet Wernli.

“It’s very hard to say what happened to that poor lady, as they are very stringent about getting on and off,” says Cheryl Michel.

“In this day and age with technology, everyone has their own coded card so not only do they know how many people are on or off, they know who the people are,” says Ron Dodd.

An FBI agent in Boston is investigating Powell’s disappearance for the United States and RCMP in Prince Edward Island, New Brunswick and Nova Scotia have also been notified.

Powell is described as a white woman with a thin build and brown, shoulder-length hair. She is roughly five-foot-six inches tall and speaks with a strong Southern accent.

Anyone with information on her whereabouts is being asked to contact Halifax Regional Police.

With files from CTV Atlantic's Kelland Sundahl