Qantas, the flag carrier of Australia, announced this week it was the target of a cyberattack that compromised data belonging to 6 million customers. The airline said it is still investigating the full extent of the data breach,

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.