The Marriott hotel chain has confirmed a data breach of its guest reservation database for the Starwood division.

Records of 500 million customers have been compromised, with information for about 327 million guests containing “some combination” of name, mailing address, phone number, email address, passport number, account information, date of birth, gender, and arrival and departure information,” according to the company.

Card payment details could also be compromised.

In a statement Marriott said: “We deeply regret this incident happened.

“Marriott reported this incident to law enforcement and continues to support their investigation. The company has already begun notifying regulatory authorities.”

Marriott is in the process of notifying customers whose records were part of the data breach.

Worryingly some records also included encrypted payment card information, Marriott Hotels can not rule out that the encryption keys had also been stolen.

The UK’s Information Commissioner’s Office said: “We have received a data breach report from Marriott involving its Starwood Hotels and will be making enquiries. If anyone has concerns about how their data has been handled they can report these concerns to