Police defuse two massive car bombs

The first - packed with petrol, nails and gas canisters - outside a nightclub in Haymarket, was "clearly linked" to a second car a few hundred yards away, police said.

The second vehicle, a blue 280E model Mercedes was found to be a bomb after being unwittingly towed to an underground car park off Park Lane. It had been taken there after being issued with a parking ticket in Cockspur Street, down the road from where the first car, also a Mercedes, was discovered.

Both vehicles contained similar materials and both were "potentially viable", Deputy Assistant Commissioner Peter Clarke told a press conference at Scotland Yard.

He said: "There was a considerable amount of fuel and gas canisters, as in the first vehicle. There was also a substantial quantity of nails. This like the first device, was potentially viable and was made safe by explosives officers. The vehicles are clearly linked."

Mr Clarke said the second Mercedes was issued with a parking ticket at about 2.30am on Friday, and was taken to the pound in Hyde Park around 3.30am. He said it had been examined by Metropolitan Police explosives officers.

The first car bomb was left outside the Tiger Tiger nightclub in Haymarket. Senior police officers said the car, primed with petrol, gas canisters and nails would have caused "carnage" if it had exploded.

The device was only discovered by chance when a passing ambulance crew noticed strange fumes coming from the Mercedes car. Paramedics were on a routine emergency call when they saw what appeared to be smoke coming from the car shortly before 2am.

Police were called and bomb disposal experts disabled the device by hand, saving crucial forensic evidence. Sources suggested one of the first officers on the scene averted disaster by disconnecting a mobile phone in the car which may have been used to trigger the explosion. But Scotland Yard dismissed the claims as "speculation".

Mr Clarke said the police were doing "everything possible to protect the public" and said there would be more police patrols. Downing Street confirmed there will be another meeting of the Government's emergency response committee Cobra on Saturday.