Device had potential to cause more devastation than 7/7 blasts
COUNTER-TERRORISM specialists were last night carrying out detailed forensic analysis on the Parsons Green device, as experts said it could have caused more fatalities than those used in the 7/7 attacks in London in 2005.
The improvised explosive device, which was contained in a 10-litre plastic bucket, exploded on a District line tube, as hundreds of commuters made their way into the centre of the capital.
But mercifully, thanks to the incompetence of the bomber, the main explosive charge failed to go off when the device was prematurely activated as the train sat at Parsons Green station in south-west London.
The bomb was contained in a white bucket, which was disguised in a plastic cool bag from the supermarket, Lidl. It appeared to have been covered with a black cloth, perhaps to try to mask the smell from any chemicals in the bucket and disguise its contents.
Images of the device, taken by quickthinking passengers, showed a string of Christmas fairy lights protruding from the top of the bucket, which one expert suggested could have been used as part of a crude timer mechanism.
Fairy lights were key to the terrorist plot launched by Zahid Hussain, a 29-year-old who planned to target the high-speed Birmingham to London railway line with a home-made bomb.
He filled the device with shrapnel and made “improvised igniters” from the decorations, but he was caught before he could carry out his attack and was jailed in May.
The lights, which would be attached to a battery and could be set to flash intermittently, would be used to deliver a charge into the detonator.
The bomber could have set the lights to flash on a delay, giving himself a short window in which to escape before the device detonated. But it is thought the detonator burst into flames prematurely, perhaps as a result of friction within the device caused by the moving train.
David Videcette, a former Met counter-terrorism officer who investigated the 7/7 attacks, said the latest bomb appeared to have many similarities with previous devices. He said: “In terms of scale this is bigger than the devices used in 7/7, so had it gone off successfully it would have caused huge loss of life. Whoever built this was not an amateur – it has many of the hallmarks of devices used by terror groups, but the use of the timer to set off the initial part of the device is something we have not seen before in the UK.”
Fortunately, the fireball from the detonator did not set off the main charge, possibly because the bomber failed to get the correct mix of chemicals needed in order to complete the chain reaction needed for an explosion.
Will Geddes, a terrorism expert, said: “My suspicion is that Parsons Green was not the intended target. If it was Paddington or Notting Hill, they are internationally recognised names.”
Sources said the bomb was packed with shrapnel, including nuts, bolts and nails to cause maximum devastation. It is thought it was a chemicalbased bomb, similar to the one used by Salman Abedi in the suicide attack on the Manchester Arena earlier this year in which 22 people were killed. It was also thought to have similarities to the bombs used to blow up Tube trains during the attacks on London in 2005.
But like the failed attacks two weeks after that, the device only partially exploded due to a problem with the main charge, likely to have been hydrogen peroxide or TATP. Hans Michels, professor of safety engineering at Imperial College London, said: “There are a lot of similarities with the aftermath of the second largely failed explosions on the London underground in 2005.
“In appearance and arrangement the remnants of the device seem highly similar to those of the hydrogen peroxide based devices of 2005. The size of the device and its containment in a plastic bucket is also the same.”
Theresa May is expected to order tech companies such as Google to crack down on extremist material following the attack. Instructions to make the fairy light bomb used by the terrorist could still be found online last night.
The Prime Minister is expected to address the issue during a summit with Emmanuel Macron, the French president, next week.
Counter-terrorism experts, meanwhile, will be assessing an apparent change in tactics, with the suspect appearing intent on escaping rather than killing himself. Last night, there was a massive manhunt under way across London for the bomber amid concerns that he could strike again, perhaps this time using a cruder method such as a vehicle or knife attack.
‘This is bigger than the devices used in 7/7, so had it gone off successfully it would have caused huge loss of life’