BT has confirmed a nationwide network problem that has affected broadband users across the country.
On social networking site Twitter, the telecoms giant said: "Sorry if you were unable to use the internet this morning, we've got a network problem affecting some customers nationwide, more updates soon".
The problem is believed to have started in the early hours of this morning. Broadband provider PlusNet, which is owned by BT, reported that the problem was affecting the following dialling code areas: 01905, 0121, 01452, 01564, 01684, 01242, 01865, 01789, 0129, 01827, 01527, 01432, 01543, 01926, 01600, 01386, 01676, 01386, 01384, 01885, 01453, 0162275 and 0127373.
Customers took to the social network – presumably using their 3G mobile phones – to express their dismay at being left without a broadband connection.
Ian Bland, who is based in Scarborough, tweeted: "Well done BT, broadband gone down here and most of the UK on supposedly the busiest day of the year for online retail... nice one".
At 10:00, communications services provider Timico updated its DSL customers by stating that "we are currently affected by a major service outage which is causing some of our customers to be presented with issues when trying to access the internet".
At 10:20, on its services updates website, BT told customers that it acknowledged the problem and was attempting to eradicate the issue.
"We're really sorry but we've got a problem at the moment nationwide, which means that some of our customers will be having trouble getting online. Customers may experience intermittent loss of connection or drop in connection.
"We're trying to fix the problem as quickly as we can," it said.
It gave an estimated time of 15:00 to fix the problem, but customers have been left unimpressed.
Caroline Hooton, based in London, tweeted: "BT now estimates fixing the broadband problem by 15:00. I won't hold my breath."
BT has since told Computing that it has already fixed the issue for the majority of its customers.
"We can confirm that a small number of broadband customers will have experienced technical difficulties this morning, following a software upgrade on our network. We have been working hard to fix the issue and have already restored service to the majority of those affected," a BT spokesperson said.
"We hope to resolve the remaining issues as quickly as possible and we apologise for any inconvenience this has caused," he added.