A 38-year-old Canadian has been arrested after police say two Australians were unwittingly used as drug mules in an "elaborate scam" involving an expenses-paid vacation to Canada.

The Australian Federal Police say a couple from Perth -- who had recently "won" a pair of tickets to Canada, including seven night’s accommodation, spending money and new luggage – alerted custom officials at Perth International Airport about concerns they had with their luggage.

Police identified them as a 64-year-old woman and 72-year-old man.

An X-ray examination showed "irregularities" in the lining of the suitcase, according to a release from the AFP. Police said three-and-a-half kilograms of methamphetamine, with a street value of $7 million, were found hidden in the couple's luggage.

"The organizers of this scam went to great lengths to provide a façade of legitimacy," AFP Perth Airport Police Cmd. David Bachi said in a statement Friday. "Thankfully the travellers contacted customs and didn't dismiss their concerns, allowing us to make the arrest."

Police said the 38-year-old Canadian, who has not been named, was arrested at Perth International Airport on Oct. 13. At the time, he had been waiting to greet the couple at the airport, police said.

Search warrants were carried out at a hotel in Scarborough, Perth, where documents linked to the holiday ticket scam were found. Police also found two suitcases similar to the ones seized at the Perth airport, electronic equipment and approximately $15,000 in cash.

The Canadian man has been charged with import a commercial quantity of a border controlled drug. The maximum penalty, if convicted, is life imprisonment.

A subsequent investigation into the ticket scam has revealed a "complex and highly-organised scam" in which older Australians appear to be targeted by a "bogus Canadian-based tour company" called AUSCAN Tours, police say.

"We will continue working with local and international law enforcement partners, targeting all elements of this drug syndicate," Bachi said.

In an interview, the Perth woman said she and her husband, who toured Vancouver and Whistler during their overseas trip, had no idea they had been duped into being drug mules.

“In the end, it seemed legitimate, so I went,” said the woman, who didn’t want to be identified.

She said the suitcases they “won” were “very nice” but a “little bit heavier.” Customs later found the illegal drugs concealed in the lining of the suitcases.

Sensing something was wrong, the woman said she was relieved when police found the drugs after she brought her concerns to authorities.

“My life could have been ruined,” she said.

The Australian Customs and Border Protection Service is warning travellers about carrying luggage on behalf of someone else.

"If you've been asked to carry something on behalf of another person, make the right choice and alert local authorities," ACBPS director of Perth airport operations Jan Hill said.

"Do not allow another person to pack your bag and do not carry luggage on behalf of another person."

With a report from CTV Toronto’s Austin Delaney