Thousands of Virgin Media customers lost their broadband connections shortly after 9pm on Monday night following a problem during routine maintenance.

The hiccup left customers across the UK without internet access or video-on-demand services, although Virgin Media claimed that broadcast television and telephone services were unaffected.

"At 9:20pm last night, customers in a number of regions temporarily lost connectivity to their broadband and video-on-demand services," said the firm in a statement.

"This occurred as a result of an error during a routine maintenance process which affected some customers' modems and set-top boxes."

It seems that the problem occurred when the modems and set-top boxes lost their IP addresses during the maintenance procedure.

The resulting flood of requests for new IPs caused Virgin Media's DCHP servers to crash, leaving many without access to the network.

"As the loss was temporary and not a network outage, it is difficult to establish the exact scale of the affected customers," the company said.

"Some customers may have noticed a loss of service as short as a few minutes, many may not have seen any loss of service at all, depending on when they were online."

The precise failure is still under investigation. Virgin Media's site stated: "Slower than usual speeds are being reported in certain areas: an upgrade to resolve this has been identified and deployment has commenced. We will update this site when roll-out has completed."