Telecoms giant BT has apologised after swathes of customers had their broadband temporarily cut off.
The internet provider's website also crashed and many customers reported the customer service line was down.
A BT spokesman confirmed the service problem, but said there was "no evidence" of a "malicious attack". Rival TalkTalk's computers were hacked in October in what was originally feared to be a mass raid on customers' personal data.
The BT spokesman said: "Large numbers of customers have been experiencing temporary issues with their broadband services this afternoon. Customers can still receive and make calls as normal.
"We've been working hard to fix the issue and are glad to report that nearly every customer affected is now reconnected, approximately two hours after the problem started.
"We apologise to any affected customers for the inconvenience.
"There is no evidence at this stage to suggest that we were subject to a malicious attack."
Customers from around the UK reported problems with their internet and landlines on social media.
Keith Pestell tweeted: "BT internet down, support lines down and website down. I did get through to India and the lady said: It's working here... really?"
Janey Godley joked: "Dear BT have you tried turning your server off for ten seconds then back on?"