Looks like it was a fairly simple brute force device. Core of gunpowder and nails, lots of gas cans around, etc. Still would have done plenty of damage. There is a second alert at the moment for a different car as well, no word if the two are related.
http://www.cnn.com/2007/WORLD/europe/06/29/london.alert/index.html
LONDON, England (CNN) -- Police in London say they have deactivated a bomb packed with nails and capable of creating huge casualties, raising renewed fears of a terrorist strike almost two years after the city was hit by deadly suicide bombers.
The device, consisting of 200 liters of fuel, gas cylinders and nails linked to a triggering mechanism, was found in a car in Haymarket, in the city's busy nightclub and theater district shortly before 2 a.m. (0100 GMT) on Friday.
British police anti-terror chief Peter Clarke said the explosives would have resulted in significant injury and loss of life had they detonated. (Watch police describe potential blast )
Clarke said a quick-thinking ambulance crew alerted police after they noticed a smoke-filled car parked close to the popular "Tiger Tiger" nightclub where they were attending an earlier incident.
Explosives officers discovered the fuel and nails attached to a "potential means of detonation," inside the vehicle. Officers "courageously" disabled the trigger by hand, he said.
Hours later, another road in central London was closed as police investigated a "suspicious" vehicle. Park Lane, an upmarket address close to Buckingham Palace and the main Oxford Street shopping area was cordoned off.
Earlier, security sources told CNN that the "relatively crude device" in the first car contained at least 200 liters, or about 50 gallons, of fuel in canisters.
"Even at this stage it is obvious that if the device had detonated, there could have been severe injuries and loss of life," Clarke said.
He said it was to early to say who was responsible, but detectives were examining footage taken by the city's extensive CCTV cameras.
Witness Daniel Weir said he was walking home from work when he noticed police had cordoned off the area around the nightclub and a nearby vehicle.
He snapped several photographs, including one that showed a canister labeled "patio gas."
"If I known what was actually ... going on, I don't think I would have been hanging about," he told CNN hours later.
British Prime Minister Gordon Brown, appointed just two days earlier in a transition of power seen as a potential spur for extremists to mount an attack, said the incident was a reminder of the dangers facing the country. (Full story)
Brown, whose predecessor Tony Blair's support for the war stoked anger among Islamic militants, said Britain faces "a serious and continuous threat" and the public "need to be alert" at all times.
The incident comes close to the second anniversary of July 7, 2005, when four Islamic extremist suicide bombers killed 52 people on London's transport system in the deadliest strike on the city since World War II.
'Rude awakening'
CNN International Security Correspondent Paula Newton said it was potentially aimed at theatergoers or nightclubbers, echoing plots recently thwarted by anti-terror police in which Islamic militants intended to attack prominent dance venues and shopping malls.
London has a long history of bomb attacks and alerts during decades of violence mounted by Northern Irish guerrilla groups. Lone attackers have also previously targeted the city's gay and immigrant communities. (Timeline of attacks)
Friday's incident could prove to be the first major test for new Prime Minister Brown, a former finance minister, who has only just appointed his cabinet, including new Home Secretary Jacqui Smith, in charge of domestic security.
"For Gordon Brown it is a rude awakening to the realities you take on as prime minister," CNN's European Political Editor Robin Oakley said. (Watch Oakley on "rude awakening" for Brown )
Smith Friday attended a meeting of Britain's so-called Cobra emergency committee -- consisting of intelligence and security chiefs -- and later briefed Brown's cabinet.
"As the police and security services have frequently said we face one of the most serious and sustained threats to our security at the moment," Smith told reporters.
Police later said they were deploying an enhanced presence to provide extra security across the capital, but said the reinforcements were not in response to a specific incident.