Vodafone U.K. has confirmed that almost 2,000 customer accounts were accessed during a system attack that took place on Thursday morning. A company spokesman said that names, phone numbers, and bank details may have been stolen.

This is the second attack on a British telecoms company within a week, following an attack on TalkTalk in which 4 million names and email addresses were stolen, along with the credit and debit card details of almost 21,000 customers.

"This incident was driven by criminals using email addresses and passwords acquired from an unknown source external to Vodafone," the Vodafone spokesman told VentureBeat.

The attackers were unable to obtain credit or debit card numbers in this attack; only bank sort-codes and the last four digits of customers' account numbers are thought to be at risk — along with their names and mobile phone numbers.

"However, this information does leave these 1,827 customers open to fraud and might also leave them open to phishing attempts," the spokesman added.

Vodafone has already begun contacting all of the customers who are affected by this attack. It's unclear at this point whether this is related to the earlier TalkTalk incident, which has already seen two teenagers arrested.