The InterContinental Hotels Group (IHG) has announced it's conducting an investigation into a payment card incident that led to a series of unauthorized charges on cards that were used at a handful of properties in the Americas.

IHG said that it's notifying guests who used their cards at a dozen hotel restaurants and bars between August 2016 and December 2016. 

So far, IHG's investigation has found that malware was installed on the servers that processed payment cards at the restaurants and bars at 12 properties. The malware searched for a handful of key data, including cardholder name, card number, expiration date and internal verification code.

Payment cards used at the front desk of those properties were not affected, the hotel chain said.

A majority of the affected properties are located in California, but the malware also hit hotels outside the mainland U.S., including Aruba, Canada and Puerto Rico.

IHG said it's currently working with leading cyber security firms to enhance its security measures.

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"It is always advisable to remain vigilant to the possibility of fraud by reviewing your payment card statements for any unauthorized activity," IHG stated on its website. "You should immediately report any unauthorized charges to your card issuer because payment card rules generally provide that cardholders are not responsible for unauthorized charges reported in a timely manner."

While troubling, payment card breaches have become more and more common at hotel chains of late, with multiple companies launching similar investigations in 2016, including Kimpton Hotels & Restaurants, HEI Hotels & Resorts and Rosen Hotels & Resorts.

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