British Airways has apologised for what they have called a very sophisticated breach of the firm's security systems.
Around 380,000 transactions were affected, but the stolen data did not include travel or passport details. The airline said personal and financial details of customers making bookings had been compromised.
The breach took place between 22:58 BST on 21 August and 21:45 BST on 5 September.
"The breach has been resolved and our website is working normally," BA said in a statement.
"We have notified the police and relevant authorities. We take the protection of our customers' data very seriously."
The British Airways hack of personal data only affects those customers who booked flights between 21 August and 5 September via British Airways website and mobile app. Any affected passengers are being contacted directly by the airline.
We are pleased to confirm that customers who booked flights directly through Travel and Transport Statesman are NOT affected by this security breach.
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