A 15-year-old boy arrested in connection with the TalkTalk cyber attack has been released on bail.

The teenager was detained in Northern Ireland on Monday and questioned on suspicion of Computer Misuse Act offences.

A Police Service of Northern Ireland spokesman said: "A 15-year-old youth, arrested in County Antrim yesterday as part of the investigation into the alleged theft of data from the firm Talk Talk, has been released on bail pending further enquiries.

"The investigation being conducted by the Metropolitan Police Cyber Crime Unit, Police Service of Northern Ireland and National Crime Agency is continuing."

The teenager had been interviewed at Antrim police station after he was arrested and a house searched on Monday afternoon.

The investigation is being carried out by the Met's cyber crime unit, the PSNI's cyber crime centre and the National Crime Agency.

TalkTalk chief executive Dido Harding has said she still was unsure how many of its four million UK customers had been affected by the attack, which affected the telecoms giant's website rather than its "core systems".

Jesse Norman, chair of the Commons Culture, Media and Sport Select Committee, is leading an inquiry into the alleged data breach.

Officers are investigating a ransom demand sent to the the phone and broadband provider by someone claiming to be responsible and seeking payment. The firm said it was not sure if the message was genuine.

The latest breach is the third in a spate of cyber attacks affecting TalkTalk in the last eight months, with incidents in August and February resulting in customers' data being stolen.