Millions of smartphone users in the UK have lost their data services after the O2 network suffered technical problems.
O2 has 25 million customers, but also provides services for the Sky, Tesco, Giffgaff and Lycamobile networks which have another seven million users.
Many users took to Twitter to complain about the difficulties, which were first reported at about 05:30.
An O2 spokesperson said a software issue identified by a third-party supplier was to blame for the outage.
“We believe other mobile operators around the world are also affected. Our technical teams are working with their teams to ensure this is fixed as quickly as possible,” she said.
“We’d encourage our customers to use wi-fi wherever they can and we apologise for the inconvenience caused.”
O2 is the second-largest mobile network in the country, behind EE.
Voice calls are unaffected by the problem.
The outage is having knock-on effects for other services that rely on the O2 network, including Transport for London’s electronic timetable service at bus stops, which has stopped working.
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