Millions of cell phone users around the world have not been able to use their smartphones after a software problem in the systems provided by Ericsson has caused serious problems.
Japanese smartphone users on the SoftBank network and British customers on O2 were frustrated Thursday by a significant disruption and a lack of clarity about when the service would resume.
The 4G network of O2 crashed around 5:00 local time in the UK, leaving millions of customers without access to data.
O2 stated in a statement: "One of our global suppliers has identified a global software problem in the system."
The mobile network said it was working with the supplier to solve the problem as quickly as possible, and also other telecommunications companies all over the world have been interrupted.
The problem with Ericsson equipment, according to two people with direct knowledge of the situation. The Swedish company is also a supplier of SoftBank in Japan.
An Ericsson spokesman declined to comment. O2 did not appoint the supplier but confirmed that it was not Huawei, the Chinese company whose chief financial officer was arrested in Canada on Saturday
O2, owned by the Spanish Telefónica, has 32 million customers in its network, including Tesco Mobile and giffgaff. O2 was at the center of a major network outage in 201
Large parts of SoftBank's mobile network remained out of service across central Japan on Thursday, after customers mainly in Tokyo and Osaka lost connectivity at 1:39 local time.
In a statement on his website, SoftBank apologized to customers and said he was "examining the cause" of the problem.
The interruption hit less than two weeks before an initial public offering scheduled for the SoftBank mobile sector, a matter of actions that will be the largest in Japan's history and has been overflowing for the retail investors.
The shares listed in Tokyo in SoftBank fell 6 percent on Thursday amid a larger sell-off, touching their intra-day low following reports of service interruption.