Qantas has sent emails to customers affected or potentially affected by a cyber attack, but none of its executives have yet fronted the media.

Australian airline Qantas says a data hack on Monday exposed the personal information of six million customers and it expects the amount stolen to be “significant.”

Australian airline Qantas said that a hacker made off with a trove of customers’ personal data including passenger names, emails, phone numbers, birth dates and frequent flyer numbers.