Guardian : Bomb plot jury shown effect of attack on gas pipelines

Bomb plot jury shown effect of attack on gas pipelines

by Ian Cobain | August 30, 2006

The potentially devastating consequences of a terrorist attack on Britain's gas pipeline network were demonstrated to an Old Bailey jury yesterday.

They were shown video footage of gas explosions which had been detonated by engineers in an attempt to assess the impact of such an attack.

In one explosion at a test site in Cumbria, the engineers used plastic explosives, and in a second they triggered a homemade device made of ammonium nitrate fertiliser and diesel fuel.

Both ripped the ground apart, sent flames more than 500 metres in the air and damaged buildings 300 metres away. During one test, plumes of flame could be seen five miles away.

The footage was shown at the trial of seven men accused of plotting to carry out a bomb attack on an unspecified target, which is alleged to have been either a nightclub, shopping centre, or high-pressure gas pipeline.

Dr John Evans, a scientist with Advantica, formerly the research arm of British Gas, told the court: "When the gas comes out of the pipe it reacts with the air and it may ignite. If the gas is released in a confined area such as a room or something with walls and a ceiling that will result in an explosion from a rapid build-up of pressure.

"That pressure has to go somewhere. In this courtroom such an explosion would be eight times what it could support and push the walls out by eight times.

"At about 15 millibars of pressure, people will be hurt. At 100 metres from the blast there will be several hundred millibars of pressure build-up."

A number of the defendants are alleged to have stored 600kg (1,323lbs) of ammonium nitrate in a London lock-up before their arrest.

Earlier, the court heard that one defendant, Omar Khyam, has admitted downloading an instruction manual on the building of a fertiliser bomb.

The jury has heard that an explosives handbook and a US military training manual were found on a computer at the home of another defendant, Jawad Akbar.

Yesterday, Joel Bennathan QC, for Mr Khyam, said: "It is my case that the documents were put on this computer by my client Omar Khyam and then deleted."

Mr Khyam, 24, of Crawley, West Sussex, denies conspiring to cause an explosion likely to endanger life or injure property between January 1 2003 and March 31 2004.

Waheed Mahmood, 34, Mr Akbar, 23, and Shujah-ud-din Mahmood, 19, all of Crawley, Anthony Garcia, 24, of Ilford, Essex, Salahuddin Amin, 31, of Luton, and Nabeel Hussain, 20, of Horley, Surrey, deny the same charge.

Mr Hussain, Mr Garcia and Mr Khyam also deny possessing 600kg of fertiliser for the purposes of terrorism, and Mr Khyam and Mr Mahmood deny possessing aluminium powder for purposes connected with terrorism.

The trial continues.