SCOTLAND YARD has uncovered evidence that Al-Qaeda has been plotting to bring down the internet in Britain, causing chaos to business and the London Stock Exchange.

In a series of raids, detectives have recovered computer files revealing that terrorist suspects had targeted a high-security internet “hub” in London.

The facility, in Docklands, houses the channel through which almost every bit of information on the internet passes in or out of Britain.

The suspects, who were arrested, had targeted the headquarters of Telehouse Europe, which houses Europe’s biggest “web hotel”, containing dozens of “servers” , the boxes which contain the information that makes up the web.

Security experts say the plot against Britain’s internet “hub” reflects the constantly changing threat from Al-Qaeda and related Islamic extremist groups.

Last year MI5 uncovered intelligence which suggested that Islamic terrorist suspects had carried out reconnaissance of the huge Bacton complex of gas terminals on the Norfolk coast. The threat led to the deployment of armed guards around the plant.

A senior Whitehall security official said the internet plotters appeared to be planning to infiltrate the “hub”, possibly to blow it up from the inside, according to evidence on a computer hard drive seized in raids on the homes of terror suspects in southern England last year.

“The Telehouse facility was the subject of intense reconnaissance. The evidence suggests that it was one of a range of options considered by the suspects,” the official said.

The discovery led Eliza Manningham-Buller, head of MI5, to set up the Centre for the Protection of National Infrastructure last month. It is a special MI5 unit to help to protect “infrastructure” sites from terrorist attacks, such as telecommunications, the internet and key utilities such as oil, gas installations and nuclear power stations.

“Without these services, the UK could suffer serious consequences, including severe economic damage, grave social disruption, or even large-scale loss of life,” the MI5 website says.

The Telehouse hub is nicknamed CTU after the counter-terrorist headquarters in the American television series 24. It is designed to provide back-up power for all Britain’s vital network services in the event of a large-scale terrorist attack elsewhere.

Yesterday the company confirmed that it was required to go on a “heightened state of alert” last year, when security officials say they uncovered the plot. It declined to discuss the threat but said it wanted to reassure its customers that it was doing everything possible to protect itself from terrorism.

Robert Harris, its technical services director, said: “Major co-location companies such as Telehouse are strategically important organisations at the heart of the internet.

“Security and business continuity are critically important. Our industry remains as alert as possible to any threat, terrorist or otherwise, and we are in regular communication with the appropriate authorities.

“The climate in 2006 required a heightened state of alert. In 2007 we remain in this heightened state of awareness to any such security threat and are in regular dialogue with the authorities.”

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