The BBC's entire network of websites, including BBC News and the iPlayer, went offline for about an hour following an unprecedented network failure.
The disruption, which happened on Tuesday evening, affected every website operated by the BBC.
An explanation for the outage was not given but Steve Herrmann, editor of the BBC news website, said in a blog post that the BBC technical support staff had revealed there had been a "total outage of all BBC websites".
“We haven't yet had a full technical debrief, but it's clear it was a major network problem. We'd like to apologise to everyone who couldn't get onto the BBC News website during that time,” Herrmann said.
Frustrated BBC visitors used Twitter to debate the reason for the outage, with some speculating that the disruption could have been caused by a cyber attack while others held the recent budget cuts responsible. BBC websites remained inaccessible from 11 pm on Tuesday evening until midnight.
IT solutions firm Siemens, which looks after the BBC websites, said that its engineers were working fast to zero-in on the problem. Siemens engineers were looking into network problems at the hosting sites in Maidenhead, Berkshire and London Docklands.