Three men have been arrested following a large-scale data breach at mobile service provider Three.

The company has revealed that names and addresses of customers as well as other details were accessed by hackers using a login to the database. The breach concerned customers who were due for an upgrade on their handsets. The information obtained meant that the newly upgraded devices could be intercepted.

The National Crime Agency said that two of the detained men are from Manchester and the third is from Kent. All three are currently on bail while enquiries are ongoing.

Three has nine million customers and is currently looking into how many customer accounts were breached, although it was keen to stress that card, bank and payment details were not accessed. A spokesman for Three said that the last month has seen an increase in hacking attempts and that the company is working with the police to investigate.

So far the company has been able to establish that around 400 smartphones have been taken in burglaries, and a further eight handsets have been stolen as a result of the breached upgrade information. Three has confirmed that steps have been taken to control data and is in the process of contacting victims.

The hacking incident is considered to be different than the hacking incident suffered by Talk Talk in October 2015, which affected more than 156,000 customers. Talk Talk had to pay a fine of £400,000 as a result of customer information being breached.