Read the warning sent out to nightclubs in full

An Islamic website predicted an attack in London just hours before two powerful car bombs were planted in the heart of the West End.

On Thursday night a message appeared on one of the most widely used jihadist internet forums saying: “Today I say: ‘Rejoice, by Allah, London shall be bombed’.”

The posting was found on the El Hesbah chat room and was left by a regular contributor who goes by the name Abu Osama al-Hazeen.

Al-Hazeen’s message began: “In the name of God, the most compassionate, the most merciful. Is Britain longing for al- Qaeda’s bombings?” He decried the recent knighthood for the author Salman Rushdie as a blow felt by all British Muslims. “We say to Britain: The Emir of al-Qaeda, Sheikh Osama, has once threatened you, and he carried out his threats,” the message reads.

CBS News said that al-Hazeen had responded to posts by other forum members who hoped an attack was imminent by saying: “Victory is very close, but you are just rushing it.”

Peter Nesser, of the Norwegian Defence Research Establishment, which monitors jihadi websites, said that the forum was an “important outlet” for militant groups and their sympathisers, but there was no way to confirm a connection.

Details of the posting came last night as police confirmed a “clear link” between two cars laden with explosives and nails and left in the same vicinity.

In an “obviously troubling” development, a vehicle towed from Cockspur Street, SW1, about the time that experts were defusing the Haymarket car bomb around the corner, was found to be just as lethal. With the thwarted attacks apparently designed to coincide, fears were heightened that they were planned by al-Qaeda.

Deputy Assistant Commissioner Peter Clarke, leading the hunt for the would-be bombers, confirmed that a blue Mercedes was issued with a parking ticket at 2.30am in Cockspur Street before being taken to an underground Park Lane compound an hour later.

He said that it was found to contain very similar materials to those in the bomb found outside the Tiger Tiger nightclub, including a large amount of fuel and gas canisters and a substantial quantity of nails.

Park Lane was shut for the day as police investigated the second suspicious vehicle, which was towed away by unsuspecting parking wardens. “These vehicles are clearly linked,” Mr Clarke said. He urged the public to be alert and report any type of threat.

Police hunting the would-be bombers were given a head-start by officers called to the pale green Mercedes outside Tiger Tiger afterambulance staff treating a clubber saw smoke coming from the car.

The officers climbed into the vehicle among gas canisters leaking vapour and removed a mobile phone that would have triggered the device. Their actions meant that police had an intact device and the car filled with fingerprints and DNA to identify the bomber. Mr Clark praised the officers for their courage and skill. He said that if the bomb had exploded “there could have been significant injury or loss of life”.

He said that the Mercedes was “in one of the busiest parts of Central London in the early hours of a Friday morning when many, many people were leaving nightclubs and other places after an evening out”.

The area is covered by one of the most sophisticated CCTV networks in the world, which will give the police sharp pictures recording when the car was parked. Although Scotland Yard officers maintain publicly that they were keeping an open mind on the background of the bomber, officers say privately that they believe that it was an Islamist terrorist attack.

Police fear that the car could mark the start of an Iraqi-style bombing campaign on London streets and say the device made is very similar to the bombs planted in Baghdad. The Times has learnt that police have been fearing an attack on a large club or bar for some time. In the past week Tiger Tiger received a 53-page document from police warning them about vehicle-borne explosives.

The document said: “It is possible that your premises could be involved in a terrorist incident. In the worst case scenario your staff and customers could be killed or injured, and your premises destroyed or damaged in a ‘no warning’, multiple and co-ordinated terrorist attack.”

The paper, which was a general warning, said: “Terrorist attacks in the UK are a real and present danger. Crowded places, including bars, pubs and nightclubs may feature in the attack plans of terrorist organisations as they are usually locations with limited protective security measures and therefore afford the potential for mass fatalities and casualties.”

The document was sent by the National Counter Terrorism Security Office to all police forces two weeks ago. They copied it to big clubs in their areas.

Key numbers

500 people were inside the Tiger Tiger nightclub when the suspect Mercedes was first noticed

60 litres of petrol were found inside the car

15 minutes spent by the new Home Secretary briefing the Cabinet

200 metre security cordon was thrown around Park Lane after another suspicious car was found

0800 789321 the anti-terrorist hotline for anyone with information about the attempted attack

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