According to BA, the stolen data did not include travel or passport information.
BORK-PRONE AIRLINE British Airways (BA) has suffered a hack that saw the financial details of its customers stolen.
BA said the breach took place between 22:58 BST on 21 August and 21:45 BST on 5 September.
BA says the breach is now resolved, but customers may have had their personal and financial information exposed if they made bookings in the last couple of weeks.
The nearly two-week long hack did not involve travel or passport details, the airline said, adding that it had launched an urgent investigation into the theft of customer data.
"British Airways is communicating with affected customers and we advise any customers who believe they may have been affected by this incident to contact their banks or credit card providers and follow their recommended advice".
Around 380,000 card payments were "compromised", it said.
"Called bank and had to cancel both mine and my wife's card. None was given", she told the Daily Telegraph.
"British Airways customers will be concerned to hear about this data breach", said consumer group's Alex Neill.
The NCA is set up to tackle the most serious and organised crime posing the highest risk to public security in Britain.
Spokespeople for British Airways declined to comment beyond their official statements.
Its chief executive said at the time it would take steps to ensure such an incident never happened again, but in July it was forced to cancel and delay flights out of the same airport due to problems with a supplier's IT systems.
Earnings after taxation flew to €1.4 billion (S$2.2 billion) in the first six months of 2018 compared with €607 million a year earlier, IAG said in a results statement.