Jean Charles de Menezes was killed by firearms officers

It heard the Brazilian was shot seven times because of "fundamental failures" in Metropolitan Police planning.

One armed officer put a gun into a colleague's chest and a Tube driver was chased down a tunnel.

The force denies breaking health and safety laws when it mistook Mr de Menezes for a suicide bomber in 2005.

Opening the unprecedented trial of the force at the Old Bailey, Clare Montgomery QC, prosecuting, said that the Metropolitan Police was subject to the same health and safety obligations as any other employer or public body in the UK.

22 JULY 2005: EVENTS 0455: Bomber Hussain Osman linked to address 0600: Surveillance team reach flats 0933: De Menezes leaves flats 0939: Tailing officers unsure who he is 1002: De Menezes reaches Stockwell Tube 1005: Armed police take over 1008: De Menezes reported shot

These laws were there to ensure public safety, she said, but a "shocking and catastrophic" failure to stick to a clear strategy to apprehend one of the 21 July 2005 bombers had left the public at risk of being blown up and ultimately led to Mr de Menezes' avoidable death.

"It was the police operation itself that invited the disaster that occurred," she said.

"We say that the police planned and carried out the operation so badly that the public was put at risk and Jean Charles was killed."

Ms Montgomery said that in fast moving events, detectives had identified one of the suspected 21 July suicide bombers, Hussain Osman, within hours of the botched attacks.

They linked him to a small block of flats in Tulse Hill, south London which was also the home of Mr de Menezes.

The fact the police ended up pointing a gun at another police man and mistaking a terrorised train driver for a bomber gives you a clue as to just how far wrong the operation had gone

Clare Montgomery QC

But when Mr de Menezes left his home and was followed, neither the officers on the ground, nor those in operational control at Scotland Yard, were certain of his identity.

One spotter told commanders it was "ridiculous" to ask him for a "percentage certainty" that the target was Osman.

"By comparing the photo of Jean Charles with a photo of Hussain Osman, you may understand why some of the officers at least thought Jean Charles might be Osman," said Ms Montgomery. "None of them said he was definitely Osman."

This uncertainty continued until the very last moments of his life when commanders at Scotland Yard and firearms officers on the ground make a series of rapid decisions which dictated who was going to try to arrest the electrician, the court heard.

Scotland Yard's operation room was noisy and staffed by tired and drained staff, the court heard. More and more officers were crowding in as news of the operation spread.

As surveillance officers sat near Mr de Menezes on the tube, firearms officers "burst" onto the platform, said Ms Montgomery. One surveillance officer, codenamed 'Ivor', alerted them to Mr de Menezes' position.

Terrified driver

"As the armed officers entered the train, Jean Charles stood up," said the lawyer. "He was grabbed by 'Ivor' and pushed back into his seat.

"Two firearms officers leant over Ivor who was holding Jean Charles and [one] put his pistol against Jean Charles' head and fired. He was shot seven times and died immediately."

At the same time, one of the armed officers physically dragged 'Ivor' onto the platform while holding a gun against his chest. Ivor shouted he was a policeman and heard more shots in the carriage.

Terrified, the tube driver fled his cab - but was chased by another armed officer into the tunnel.

Ms Montgomery said: "You may think, members of the jury, that the fact the police ended up pointing a gun at another police man and mistaking a terrorised train driver for a bomber gives you a clue as to just how far wrong the operation had gone."