London resident Mark Witby was a passenger who saw police shoot De Menezes five times in the head at point-blank range:
"The train was sitting in the station with the doors open, waiting to pull out. It seemed to be taking quite a long time," Witby said. "And then I heard all this 'get down, get out.' And I looked at my right and saw the guy running onto the train. He was running so fast that he sort of half-tripped. And then, bang, bang, bang, bang, bang. Five shots."
Shortly after the shooting, London Metropolitan Police Chief Ian Blair said De Menezes' apartment building had been under surveillance as part of an investigation into four attempted bombings the day earier. Blair initially said De Menezes was thought to be linked to those attempted bombings and it was feared that he was hiding explosives beneath his clothes.
"The information I have available is that the shooting is directly linked to the ongoing and expanding antiterrorist operation. I need to make clear that any death is deeply regrettable, but as I understand the situation the man was challenged and refused to obey police instructions," Blair said.
London Mayor Ken Livingston initially defended the shooting as part of a new "shoot-to-kill" antiterrorism policy in cases where police think a suspect may be attempting to carry out a deadly attack:
"If you are dealing with some one who might be a suicide bomber. If they remain conscious they could trigger the plastic explosives -- or whatever might be on them. And therefore overwhelmingly the likelihood is that in those circumstances it will be a shoot-to-kill policy," Livingston said.
But De Menezes was not carrying any explosives. And detectives later established he was not connected to the attempts to blow up three Underground trains and a bus in the capital the day before. The Metropolitan Police say an inquest will be opened into his death -- which they described as a "regrettable tragedy."
British Muslim groups say the mistaken shooting has worried many Muslims who already fear a backlash against their community as a result of the London bombings of 7 July and the attempted bombings of 21 July.
Inayat Bunglawala, a spokesman for the Muslim Council of Britain, said: "This is a very disturbing aspect, particularly for Muslims, because they will now feel that if they are suspects then the same thing might happen to them. And I believe it has a knock on effect on getting them to cooperate with the security services."
The Muslim Council of Britain says some Muslims in London are afraid to carry backpacks or ride public transport out of fear of how police will react.
The group says that in the early days after the 7 July bombings, London police earned credibility and confidence by emphasizing the difference between ordinary Muslims and radical Islamic terrorists. But the group says that confidence has been undermined by the 22 July mistaken shooting -- and the implications of the new shoot-to-kill policy.
London police are emphasizing that the success of their investigation relies on help from London's Muslim community. They are issuing pleas for continued cooperation in their manhunt.
Although two suspects have been detained by authorities in connection with the 21 July attempted bombings, there is no confirmation that those men are linked to the attacks. That means at least two of the attackers -- and potentially all four -- are still at large.
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