A 15-year old boy in Northern Ireland has been arrested in connection with the cyber attack on TalkTalk.
Scotland Yard said a house in County Antrim was searched at around 16:20 BST on Monday. The boy was arrested on suspicion of Computer Misuse Act offences and has now been released on bail pending further enquiries.
A criminal investigation was launched by the Metropolitan Police last week after TalkTalk said its website had been hacked, putting its four million customers' data at risk.
However, over the weekend, TalkTalk chief executive Dido Harding said the attack was "smaller" than first thought.
TalkTalk's share prices dropped by 12% on Monday as customers grew increasingly frustrated over the company's handling of the attack. Some have complained that TalkTalk has not contacted them and others have criticised the company for not waiving its cancellation fee in the wake of the hack.