A man shot dead by police hunting the bombers behind Thursday's London attacks was a Brazilian electrician unconnected to the incidents.
Jean Charles de Menezes (far right), pictured with friends
The man, who died at Stockwell Tube on Friday, has been named by police as Jean Charles de Menezes, 27.
Two other men have been arrested and are being questioned after bombers targeted three Tube trains and a bus.
Police also said a suspect package found in north-west London on Saturday may be linked to Thursday's attacks.
Scotland Yard said Mr Menezes, who lived in Brixton, south London, was completely unconnected to the bomb attacks and added: "For somebody to lose their life in such circumstances is a tragedy and one that the Metropolitan Police Service regrets."
The Brazilian government has expressed its shock at the killing and Brazil's foreign minister Celso Amorim is on his way to London to get an explanation from foreign secretary Jack Straw.
In a statement the government said it "looks forward to receiving the necessary explanation from the British authorities on the circumstances which led to this tragedy".
The shooting is being investigated by officers from Scotland Yard's Directorate of Professional Standards, and will be referred to the Independent Police Complaints Commission.
The family of Mr Menezes told the Brazilian media there was nothing in his past which would give him a reason to run from police.
Mr Menezes' cousin, Alex Alves, told O Globo television: "I asked that the body be released as quickly as possible, we need to bring him to Brazil, which is what the family wants".
"He does not have a past that would make him run from police," he said.
Mr Alves said Mr Menezes, who was from the town of Gonzaga in Minas Gerais state, had lived in London legally for at least three years and was employed as an electrician. Civil rights groups have called for a full inquiry into the shooting.
Meanwhile Dr Azzam Tamimi from the Muslim Association of Britain told BBC News the police should review their procedures.
"Frankly it doesn't matter whether he is a Muslim or not, he is a human being.
"It is human lives that are being targeted whether by terrorists or whether in this case unfortunately, by people who are supposed to be chasing or catching the terrorists."
The Mayor of London, Ken Livingstone, said: "The police acted to do what they believed necessary to protect the lives of the public.
"This tragedy has added another victim to the toll of deaths for which the terrorists bear responsibility."
A package was found by a member of the public in bushes in Little Wormwood Scrubs on Saturday morning.
A Scotland Yard spokesman said: "Explosives officers attended the scene. An initial examination suggests that the object may be linked to devices found at four locations in London on July 21."
Police said it would be subject to "detailed forensic analysis".
Police have also raided a house in Streatham Hill, south London, in connection with the failed attacks.
Police cordoned off a 200-metre area around the station
Meanwhile the News of the World newspaper has offered a £100,000 reward to catch the second wave of London bombers.
Scotland Yard said they had been contacted by over 500 members of the public following the release of CCTV footage of four suspects.
Detectives said they were hopeful of useful lines of inquiry coming from the calls and e-mails.
1: Witnesses report seeing up to 20 plain clothes police officers chase a man into Stockwell Tube station from the street
2: One person says the man vaulted the automatic ticket barriers as he made his way to the platforms
3: The most direct route is via this escalator or the staircase that sits alongside it
4: Police challenge the man but he apparently refuses to obey instructions and after running onto a northbound Northern line train, he is shot dead