Relatives of Jean Charles de Menezes today described the Metropolitan Police as a "Laurel and Hardy" outfit and intensified calls for Sir Ian Blair to resign as Commissioner.

The family said that Sir Ian, the police chief, must take personal responsibility for the "catalogue of errors" which led to the 27-year-old Brazilian electrician's shooting on board a Tube train, and Scotland Yard's subsequent attempts to "cover up" the circumstances surrounding his killing.

Alessandro Pereira, 25, the dead man's cousin, described the family's suffering in the wake of Mr de Menezes' killing on July 22 by armed police who mistook him for a suicide bomber. He said that he believed police had subsequently told "lie after lie" in an attempt to cover up their mistakes.

"I have always believed that those who break the law should be punished and some people have broken the law," said Mr Pereira.

"They have killed Jean and then told lies. They must face justice. We want to see all those responsible brought to justice. We want to see them prosecuted."

He told the conference in Stockwell, south London: "Jean came to London full of optimism and hopes. He loved London. He loved its vibrancy. He loved the fact that it was home to people from all over the world. He was so happy to call it home.

"He was going to work on the Tube like millions of us do every day, except that on July 22 as he went to work he was murdered, an innocent man.

"The people who killed him were police officers. I want the people of London to imagine hearing that your son, your brother or your father had been killled on the Tube. Shot dead."

Although softly spoken, his anger was unmistakable: "I then want you to think how we felt when we were told he was a suspected terrorist. That he looked like a suicide bomber. That he was wearing a big jacket. That he ran from police.

"I want Ian Blair to think how it was to phone our family in Brazil and tell them that their son was dead. That he was killed in such a way. We had to answer my family's questions about how and why he died.

"I want Ian Blair to imagine how we felt having to listen to the lies about why he is dead. To see Ian Blair on television telling those lies.

"The police knew he was innocent yet they let my family suffer, Ian Blair let us suffer for three weeks. We have had to listen to lie after lie about Jean and how he was killed.

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