Update: O2 has now claimed that its 2G and 3G services are fully restored, writing on its Twitter page that customers should be able to access all services as normal.
O2 has told customers affected by its ongoing network outage to try turning their phones off in an effort to kick-start services again.
The outage first hit the network around 1pm on Wednesday and was still affecting customers across the country into Thursday morning.
On its status page O2 said that as of 8am on Thursday services on its 2G network were restored which should allow voice services to return.
It added that 3G capabilities could be kicked into life using the classic 'switch it off and then on again' tactic.
"Our 3G service is starting to restore and customers should expect to see a gradual return of data services as the day progresses. Customers affected may wish to try switching their mobile phones off and on as service returns," it said.
The firm apologised for the issue but did not supply any more information on what caused the outage.
The incident has left scores of customers without access to basic services with many complaining they will leave the network unless they receive a refund.
"O2 have let thousands of customers down. We are basically paying our money for days without service. They need to take a hike or offer their customers some money back or their deposits they had to pay if they had to take out a contract," wrote one V3 reader.
Another, from Fife, said he had been without service for over a day and would move to another network if they issue was not fixed by Thursday.
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