WestJet says it is working with police in Calgary and the RCMP cybercrime unit after some members' profile data were disclosed online.

In a statement issued late Friday, the Calgary-based airline said that the profile data of some WestJet Rewards members were disclosed online "by an unauthorized third party."

WestJet says no credit card or banking information was disclosed in the privacy breach, but the Office of the Information and Privacy Commissioner of Alberta and the federal privacy commissioner have been informed of the incident.

The company also said it has taken "immediate steps to secure affected systems."

WestJet didn't offer any detail on what kind of information was in the profile data or exactly how many rewards members may be affected by the breach.

"The privacy and protection of our guests' information is a matter we take very seriously and we have worked swiftly and aggressively to resolve this incident," Craig Maccubbin, WestJet executive vice-president and chief information officer, said in the statement.

"WestJet is in the process of contacting affected guests and we deeply regret any inconvenience this may cause."