More than a dozen hotels in the Middle East are among Hyatt operated properties worldwide which were affected by a malware breach at the group late last year, the American hotelier has confirmed.
The Chicago-based firm said a previously reported malware attack to steal payment card data affected 250 hotels between August 13 and December 8, 2015.
The hotel operator listed affected locations worldwide and the period when they were at risk, on its website.
"We do not know the number of customers affected at this time," company spokeswoman Stephanie Sheppard was quoted as saying by Reuters.
Hyatt said it identified unauthorised access to data on cards used at certain Hyatt-managed locations, primarily its restaurants.
The company also said the "at-risk window" for a limited number of locations began on or shortly after July 30.
The malware was designed to collect data such as cardholder name, card number, expiration date and internal verification code, the company said.
Hyatt said it has notified the appropriate country and state regulators and is working with the US Federal Bureau of Investigation.
Hyatt said it has arranged an identity protection and fraud detection firm to provide one year of free services to affected customers and has set up a Q&A page on its website to help customers who may be affected.
The company disclosed in December that its payment processing system was infected with malware but did not mention how long its network was infected.
Hyatt, controlled by the billionaire Pritzker family, is the fourth major hotel operator to warn of a breach since October.
Hilton Worldwide Holdings and Starwood Hotels & Resorts Worldwide disclosed attacks on payment processing systems in November.
Donald Trump's luxury hotel chain, Trump Hotel Collection, also confirmed the possibility of a data security incident.
Below is a list of all the Hyatt-managed properties in the Middle East affected by the breach, and the dates payment details were at risk:
Abu Dhabi: Hyatt Capital Gate Abu Dhabi - 8/13/2015 - 10/14/2015
Abu Dhabi: Park Hyatt Abu Dhabi Hotel and Villas - 8/13/2015 - 12/8/2015
Amman: Grand Hyatt Amman - 8/13/2015 - 12/8/2015
Doha: Grand Hyatt Doha - 8/13/2015 - 12/8/2015
Dubai: Grand Hyatt Dubai - 8/13/2015 - 10/14/2015
Dubai: Hyatt Place Dubai/Al Rigga - 8/13/2015 - 10/14/2015
Dubai: Hyatt Place Dubai/Baniyas Square - 8/13/2015 - 10/14/2015
Dubai: Hyatt Regency Dubai - 8/13/2015 - 12/8/2015
Dubai: Hyatt Regency Dubai Creek Heights - 8/13/2015 - 10/14/2015
Dubai: Park Hyatt Dubai - 8/13/2015 - 10/14/2015
Jeddah: Park Hyatt Jeddah – Marina, Club and Spa 8/13/2015 - 12/8/2015
Makkah: Hyatt Regency Makkah - 8/13/2015 - 10/14/2015
Muscat: Grand Hyatt Muscat - 8/13/2015 - 10/14/2015
South Sinai: Hyatt Regency Sharm El Sheikh Resort - 8/13/2015 - 10/14/2015