TalkTalk

Police have arrested a 15-year-old boy in Northern Ireland in connection with the cyberattack on UK broadband provider TalkTalk last Wednesday.

TalkTalk warned its 4 million customers on Friday that it had been hit by a " significant and sustained cyberattack" that might have left their data at risk. Over the weekend the company recruited defence and security company BAE Systems to carry out an investigation alongside the police, after the company received a ransom demand from the person claiming to be the perpetrator.

A teenage boy was arrested on suspicion of Computer Misuse Act offences early on Monday evening, London's Metropolitan Police said, and is now being held in custody ahead of questioning at a police station in County Antrim, Northern Ireland. A search warrant has been issued for a nearby address.

TalkTalk has become another example of how companies that possess vast amounts of personal data are vulnerable to cyberattacks. The company's share price fell by 12.3 percent on Monday in the wake of the hack, Reuters reports, and many customers have expressed outrage that much of their data had not been protected using encryption. It's still unclear whether customers have been directly affected, but the attack does make a strong case for taking a belt-and-braces approach to security and properly encrypting data.

The company is seeking to reassure customers that hackers have not had access to their debit and credit card numbers and cannot access their bank accounts, even though they may have been able to get hold of their account details and sort codes. The company is still seeking to ascertain and limit the extent of the damage, but said the amount of data that had been exposed was lower than first feared.

"We know this has been a worrying time for customers and we are grateful for the swift response and hard work of the police. We will continue to assist with the ongoing investigation," TalkTalk said in a statement following the arrest.

Executives from the broadband provider will be summoned by MPs to answer questions about the hack, with a parliamentary inquiry to be launched by Jesse Norman MP, chairman of the culture, media and sport select committee.

TalkTalk did not immediately respond to a request for further comment.