Hotel chain Best Western has downplayed concerns over a recent hack attack that was reported to have put at risk the personal details of all its customers since 2007.

According to a report in the Sunday Herald, an unknown Indian hacker had managed to gain unauthorised access to Best Western’s databases, which contain the names, addresses and credit card numbers of international customers.

However, in an email sent to UK customers on Tuesday, the hotel group said that the Herald’s claims were “grossly unsubstantiated”, and that only 10 customers had been affected.

“We can confirm that on 21 August a single hotel in Germany was compromised by a virus. The compromise permitted access to reservations data for that property only,” wrote David Clarke, chief executive, Best Western Hotels Great Britain (GB). “This has affected only ten customers who are currently being contacted to offer our assistance, none of these were GB customers. There is no evidence of any unauthorised access to any other customer data.”

He added that Best Western complies with the Payment Card Industry Data Security Standard for secure online payments to protect customer information. The hotel chain is now working with the FBI and other international authorities to investigate further.