TORONTO -- Canadians who stayed at Marriott International Inc. and Starwood Canada ULC hotels are taking legal action against the companies following a security breach.

At least three proposed class actions have been launched in Toronto and Montreal against the U.S.-based company that recently revealed hackers stole contact, credit card, passport and travel information belonging to as many as 500 million guests over four years.

The plaintiffs in the actions, which have yet to be certified, are accusing the company of negligence because they say Marriott and Starwood were "reckless" with and did not safeguard personal information.

"It is deeply concerning that Marriott appears to have failed in implementing or maintaining reasonable security measures to protect the integrity of its guests' personal information," said Sajjad Nematollahi, a lawyer at Siskinds LLP, in an email to The Canadian Press.

"The businesses' failure to protect the individuals' personal information come at grave costs and result in significant risks to ordinary citizens, for which we believe the wrongdoers must be held accountable."

Nematollahi is representing Glen Winder, an Ontario-based member of Starwood's Preferred Guest loyalty program, in a class-action filed with the Ontario Superior Court of Justice.

The suit is seeking damages and a declaration that Marriott and Starwood "intentionally or recklessly...invaded the private affairs" of Winder and other Canadians in a "highly offensive way" that caused "distress, humiliation or anguish."

Marriott declined to discuss the cases or accusations, saying the company does not comment on pending litigation.

Meanwhile, Zachary Schnarr of Toronto and lawyers at Koskie Minsky LLP are asking for damages on behalf of all Canadian Marriott customers whose data was improperly accessed.

In a court filing Schnarr said he provided the company with his personal information when a reservation was made for him at the Westin Hotel in Toronto in September and that Marriott and Starwood were aware their actions would have a "significant adverse impact" on guests.

"The defendant's conduct was high-handed, reckless, without care, deliberate," he said in the Ontario Superior Court of Justice filing.

Another Starwood loyalty program member, Won Kil Bai, has filed a class action in the Superior Court of Quebec through lawyers at Woods LLP for an unspecified amount.

Marriott and Starwood, which have refused to share how many Canadians may have had their data breached, operate 77 former Starwood branded hotels in Canada.

Marriott purchased Starwood two years, becoming the operator of brands including W Hotels, St. Regis, Sheraton and Westin.

The company has set up a hotline for guests who suspect their personal information has been breached to receive more information on the incident.

The breach is believed to be among the largest data breaches on record.