Some 12.6 million cases involving the leak of personal information were confirmed or suspected in the nation last year due to cyberattacks against companies and other entities, a Kyodo News survey showed Monday, affecting roughly 1 in 10 people.

The figure marked a sixfold increase from the 2.07 million cases in 2015, with a massive personal data leak incident involving Japanese travel agency JTB Corp. owing much to the rise. The tally also showed that credit card information was often targeted.

The tally is based on incidents that were made public last year. But an information security expert said there may be a lot more.