Mobile customers on the network Three have reported that their service has completely failed.
Users have reported having no data or signal after a network failure last night.
According to website Downdetector, which offers a live overview of outages across different networks, said the problems began at 11.30pm last night.
MORE: Employees' 'confidential' data feared stolen from Bernard MatthewsNorwich is one of the cities showing up as filing the most reports to Three, along with Manchester, London and Birmingham.
This morning, Three said: "We're currently experiencing technical difficulties with voice, text and data, meaning some of you will be experiencing intermittent service. Please accept our apologies, we're sorting this out right now."
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