UPDATE: TalkTalk has revealed that 1.2 million customer email and phone numbers and 21,000 bank details were stolen in the cyber-attack.
The ISP previously stated that the amount of details stolen was significantly lower than expected and today has provided specific numbers.
In an update, TalkTalk said that alongside the 21,000 bank account numbers and sort codes, less than 28,000 obscured credit and debit card details and less than 15,000 customer dates of birth were taken.
That's on top of the 1.2 million customer names, emails, and phone numbers.
The firm reassured customers that the credit and debit card details cannot be used for financial transactions.
A 16-year-old boy from west London has been arrested in connection with last week’s cyber-attack on ISP TalkTalk.
In a press release, Scotland Yard explained that the boy was arrested on October 29 on suspicion of offences under the Computer Misuse Act and has since been bailed.
A 15-year-old boy was arrested and bailed in Northern Ireland on Monday this week, making this the second arrest in connection with the hack which threatened four million UK customers.
Police made the latest arrest after searching an address in Feltham. Officers also searched a residential address in Liverpool.
It was originally thought that the attack was the work of a Russian Islamist group, although this was never confirmed.
An ongoing investigation by TalkTalk and the Metropolitan Police Cyber Crime Unit has thus far established that the hack may not have been as bad as originally feared.
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In an update earlier this week, the company reassured customers that although their website was hacked, their “core systems” were not.
Sensitive customer information such as passwords and important banking details were therefore unlikely to have been accessed by the hackers.
There is still some risk to customers from criminals calling and posing as bank staff in efforts to gain enough information to access their bank accounts.
Investigations are ongoing.
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