Police arrested a 15-year-old boy over a cyber attack on telephone and internet provider TalkTalk, feared to have breached the data of millions of Britons, Scotland Yard said on Monday.
The teenager was arrested and held for questioning in Northern Ireland, on suspicion of Computer Misuse Act offences, according to the Metropolitan Police.
"An arrest has been made in connection with the investigation into alleged data theft from the TalkTalk website," a spokesman for Britain's Metropolitan Police said.
The boy was apprehended during a raid in County Antrim by Northern Ireland police officers working with Metropolitan Police Cyber Crime Unit detectives.
"At the address, a 15-year-old boy was arrested on suspicion of Computer Misuse Act offences," the spokesman added.
"He has been taken into custody at a County Antrim police station where he will later be interviewed. A search of the address is ongoing and inquiries continue."
More than a tenth of the value of TalkTalk was wiped off the London Stock Exchange on Monday as traders reacted to the breach, the third cyber attack in eight months on TalkTalk in which customers' data has been stolen.
The company has said it is unsure how many of its four million customers in Britain were affected, but said that information including customer names, addresses and bank details could have been compromised.
The attack was described as "significant and sustained" by the company, which said that not all customers' data was encrypted.
"TalkTalk can confirm that we have been informed by the Metropolitan Police of the arrest of a suspect in connection with the cyber attack on our website on October 21." a TalkTalk spokesman said.
"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 in the ongoing investigation."
Police are investigating a ransom demand that was sent to TalkTalk purporting to be from the hacker, though the firm is unsure if the demand for money was genuine.
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