The huge explosion at Buncefield oil depot in Hemel Hempstead on Sunday 11 December that rocked the south of England has caused a number of UK websites offline and IT companies to close their headquaters for the day.

The fierce explosion - the largest in peacetime Britain - damaged a nearby a data center operated by Northgate Information Services as well as the offices of Kodak and Dixons Store Group.

A statement from Northgate indicated that backup equipment was unusable. "The fabric of the building and the fixtures and equipment inside have been badly damaged", Northgate said. "The back-up systems that were in place have also been rendered inoperable”.

The data center housed a number of popular UK website destinations including hi-fi specialists Richer Sounds and the Labour Party's official website.

The Party has set up a temporary site at PIPEX Communications while it seeks to recover the files for its site. The temporary site states:

“Welcome to the Labour Party website. The normal site is temporarily unavailable following an explosion at Buncefield oil depot in Hemel Hempstead on Sunday 11 December.

"Part of the offices of our hosting company were extensively damaged, resulting in the loss of our site.

"We will be back online as quickly as possible”.

The explosion also forced DSG International, which trades as Dixons, Currys and PC World to close its Hemel Hempstead HQ.

Furthermore digital camera manufacturer, Kodak was affected by the blast. Its sales and marketing offices face the oil depot. It was forced to close its site for the day.

"We are not sure how much damage has been done, as we haven't been able to access the offices to assess the damage yet”, said a spokesman for the camera company.

Both companies have reported “no disruption to trading”.