A 17-year-old from a town in England has been arrested over the recent cyberattack on Transport for London (TfL), the UK National Crime Agency announced on Thursday.

The alleged hacker was detained on September 5 on suspicion of Computer Misuse Act offenses and has since been released on bail. 

The teen has not been named, but the NCA has specified that the suspect is a male from the town of Walsall.

“We have been working at pace to support Transport for London following a cyber attack on their network, and to identify the criminal actors responsible,” said Deputy Director Paul Foster, head of the NCA’s National Cyber Crime Unit.

TfL was hit by a disruptive cyberattack on September 1. While the incident did not impact actual transportation, some services have been taken offline, including live arrival information, applications for new Oyster photocards, and journey history for contactless payments. 

In addition, the London transport network operator informed customers that it’s unable to issue refunds for incomplete pay-as-you-go journeys, and noted that many of its workers have limited access to systems, which results in delays to online inquiry responses. 

While TfL initially said it had no evidence that customer data had been compromised, the latest statement reveals that some customer data was in fact accessed by the hacker. 

“This includes some customer names and contact details, including email addresses and home addresses where provided,” TfL said. “Some Oyster card refund data may have been accessed. This could include bank account numbers and sort codes for a limited number of customers (around 5,000).”

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