A senior surveillance officer has admitted tampering with evidence in the Jean Charles de Menezes inquest.

The Independent Police Complaints Commission (IPCC) launched an investigation after the Special Branch officer, named only as Owen, accessed the computer notes he made at the time of the shooting and deleted a line last week.

He said he wiped a "wrong and misleading" entry that recorded Deputy Assistant Commissioner Cressida Dick saying: "Can run on to tube as not carrying anything. Persuaded by U/I male amongst management."

Owen said he made the change after he "flicked through" his notes and saw there were "a few mistakes". He insisted it was not done on the orders of senior officers.

Owen told the jury: "On reflection, I looked at that and thought I cannot actually say that.

"I have removed a line I believed was wrong and gave a totally false impression. The detail changes do not materially affect the statement."

An IPCC spokesman said: "This matter will be subject to an independent investigation and we are not in a position to comment further at this stage."

Ms Dick has claimed she believed Mr de Menezes posed a "great threat" as officers pursued him on July 22, 2005.

The 27-year-old Brazilian electrician was killed by specialist firearms officers who mistook him for bombing suspect Hussain Osman after boarding a train at Stockwell Tube station.

Earlier, Detective Inspector Merrick Rose said he could not recall whether officers discussed photographs which could have stopped them mistaking Mr de Menezes for Osman.

He said surveillance of the July 21, 2005 attackers on a camping trip in the Lake District the previous year was identified in a briefing, but he could not remember if pictures of Osman were mentioned before the Brazilian electrician was killed.

Instead, the inquest heard, officers relied on a gym card photograph and CCTV images before shooting dead the wrong man.

Mr Rose spoke after a senior surveillance officer, named only as Pat, denied he had told police chiefs Mr de Menezes was a suspect.

Ms Dick claimed Pat said "they think it's him" and "he's very jumpy" as officers closed in on Mr de Menezes.

But Pat, the principal link at New Scotland Yard between surveillance and Ms Dick, said Mr de Menezes remained only "possibly identifiable with" Osman throughout the chase.

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