A hacker gained access to personal information from more than 100 million Capitol One credit applications, the bank said on Monday as federal authorities arrested a suspect.

The data breach has affected around 100 million people in the US and 6 million in Canada.

The hacker got information including credit scores and balances plus the social security numbers of about 140,000 customers, the bank said. It will offer free credit monitoring services to those affected.

Paige A Thompson, who also goes by the Twitter handle “erratic”, was charged with a single count of computer fraud and abuse in US district court in Seattle. Thompson made an initial appearance in court and was ordered to remain in custody pending a detention hearing Thursday.

The FBI raided Thompson’s residence Monday and seized digital devices. An initial search turned up files that referenced Capital One and “other entities that may have been targets of attempted or actual network intrusions”.

A public defender appointed to represent Thompson did not immediately return an email seeking comment.

Capitol One, based in McLean, Virginia, said on Monday it found out about the vulnerability in its system on 19 July and immediately sought help from law enforcement to catch the perpetrator.

According to the FBI complaint, someone emailed the bank two days before notifying it that leaked data had appeared on the webhosting site GitHub.

And a month prior, the FBI said, a Twitter user who went by “erratic” sent Capitol One direct messages warning about distributing the bank’s data, including names, birthdates and social security numbers.

Capital One said it believes it is unlikely that the information was used for fraud, but it will continue to investigate.

Capital One Financial, the nation’s seventh-largest commercial bank with more than $370bn, is the latest US company to suffer a major data breach in recent years.

In 2017, a data breach at Equifax, one of the major credit reporting companies, exposed the social security numbers and other sensitive information of roughly half of the US population.

Last week, Equifax agreed to pay at least $700m to settle lawsuits over the breach in an agreement with federal authorities and states thatincludes up to $425m in monetary relief to consumers.