Hackers have stolen personal information on about 15 million T-Mobile US customers and applicants.
The breach was at a unit of the credit agency Experian, which T-Mobile uses to process information on subscribers.
Names, birth dates and social security numbers are among data stolen, but not financial details.There have been a string of high-profile hacks of businesses and other organisations in recent years affecting millions of people, including adultery website Ashley Madison, Sony Pictures, and retailers such as Home Depot, Target, and eBay.T-Mobile is now the third biggest mobile firm in the US, having surpassed Sprint this year.
