A firearms officer involved in the shooting of Jean Charles de Menezes shot a 42-year-old man during a police operation in Kent.
The man was shot on Tuesday at a building society in New Romney
The victim, Robert Haines, died after the incident at a Nationwide building society in New Romney.
Scotland Yard's CO19 firearms unit were supporting Flying Squad officers as they tackled a suspected armed robbery.
Mr Menezes was shot dead after police mistook him for a suicide bomber at Stockwell Tube station in July 2005.
The police officer involved had been taken off firearms work after the Stockwell shooting but returned to armed duty after the Crown Prosecution Service decided he would not be prosecuted.
Scotland Yard confirmed a police officer involved in the New Romney incident had been relieved of firearms duties, pending an inquiry.
The Independent Police Complaints Commission (IPCC) has also begun an investigation into the shooting.
The family of Jean Charles de Menezes expressed "shock and disbelief" that officers involved in the Stockwell shooting "had been handed back their guns as if nothing has happened".
Mr de Menezes was shot dead at Stockwell Tube station
A statement said: "Sir Ian Blair [Metropolitan Police Commissioner] might have hoped he could sweep Jean's death under the carpet but when the same mistakes keep being made, he has to be held responsible."
The dead man was named as Mr Haines by the Independent Police Complaints Commission, which is investigating the circumstances of the shooting.
He was injured at about 2000 GMT and died later at the William Harvey Hospital, in Ashford.
Three men were arrested and a sawn-off shotgun was recovered during the operation but no officers were injured.
The shooting in New Romney was related to an incident in Hamstreet, near Ashford, Kent, on Tuesday, where residents said shots were also fired.
The Metropolitan Police said in a statement: "The Specialist Firearms team (CO19) involved in the Flying Squad operation in Kent did include officers from the same team who were involved in the Stockwell shooting in July last year.
"The Met has a small cadre of specialist highly-trained firearms officers who last year were deployed to 2,529 incidents and were involved in 938 pre-planned operations."
The statement said they performed "an extremely difficult but vital function" and it was "extremely rare" for officers to fire their guns.
The Metropolitan Police Service faces a trial under health and safety laws following the shooting of Mr de Menezes.
His family have also launched a legal action challenging a decision not to charge individual officers over his death.