The investigation is being carried out by the Metropolitan Police's cyber crime unit, the Police Service of Northern Ireland's cyber crime centre and the National Crime Agency. The latest breach is the third in a spate of cyber incidents affecting TalkTalk in the last year. Police confirmed that officers have also carried out a search at a residential property in Liverpool in connection with the cyber attack. TalkTalk said it had been subjected to a "significant and sustained" attack on its website on October 21, which prompted fears that millions of people may have had their bank details st olen. The telecoms giant has since said the data hacked was "significantly less than originally suspected" with fewer than 21,000 unique bank account numbers and sort codes accessed. Fewer than 1.2 million customer email addresses, names and phone numbers were breached, along with fewer than 28,000 obscured credit and debit card details, and fewer than 15,000 customer dates of birth, the company said.