British Airways Says Data Breach Larger Than Estimated

Announcement came after Cathay Pacific said 9.4 million passenger records were compromised in a separate attack

British Airways parent International Consolidated Airlines Group SA on Thursday said a cyberattack on passenger data this year was far larger than first estimated.

The announcement came only hours after Cathay Pacific Airways Ltd., one of Asia’s largest airlines, said it had suffered a massive data breach, highlighting the difficulties airlines can have in safeguarding travel records.

IAG...