This article is more than 1 year old

This article is more than 1 year old

More than 30 million customers of mobile providers including O2, Tesco Mobile and Sky Mobile were unable to get online on Thursday, with many also unable to make or receive phone calls, after a technical fault caused a UK-wide outage unlikely to be fixed until Friday morning.

The problem hit O2’s entire network and also affected companies that use its platform, including its subsidiary Giffgaff and Lycamobile. The blackout of 3G and 4G services, which prevented customers from getting online on their phones, began at about 4am on Thursday.

O2’s chief executive, Mark Evans, told the BBC the company was confident service would be fully restored by Friday morning.

“We’ve let our customers down and I’m sorry for that,” he said. O2’s equipment supplier, Swedish firm Ericsson, admitted that its software had caused the problem.

O2, which has about 25 million UK customers, initially said voice calls were still working but later admitted customers could not make calls due to the volume of demand on its network.

“We have hundreds of people from both Ericsson and O2 working around the clock to identify the issue … we’re confident we know what the issue is,” Evans told the BBC on Thursday.

TfL Bus Alerts (@TfLBusAlerts) Countdown Systems - there are reports that live bus updates to our Countdown Systems has gone down. The company that updates the data to our network of Countdown Systems is currently experiencing difficulties in providing this service. This issue is being investigated.

“We are starting to restore the network this evening and Ericsson has given the assurance that by tomorrow morning it will have been fully restored.”

The company, the UK’s second largest mobile phone network, said the problem with Ericsson software was global and had also affected other mobile operators in 11 countries around the world.

“We’re aware that our customers are unable to use data this morning,” it said on Thursday morning. “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.”

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The outage has also affected services such as Transport for London’s live updates of bus arrival times at stops across the capital, which relies on O2’s network for data updates.

In October, O2 apologised for a major network outage affecting customers across the UK. The company said at the time that the issue was fixed within 40 minutes.

O2’s rivals including Vodafone, Three and EE have also suffered nationwide outages affecting customers in the past year. In 2012, O2 was at the centre of a major network outage when customers were not able to access services for 25 hours.