A florist who stabbed to death an armed intruder at his shop in Greater Manchester will not be charged, the Crown Prosecution Service has said.
Cecil Coley, 72, was confronted by four men with guns and a knife at his shop in Old Trafford on 26 July.
Gary Mullings, 30, of New Moston, was fatally stabbed. Mr Coley was later arrested on suspicion of his murder.
But prosecutor Nazir Afzal said he was now satisfied Mr Coley had acted "in reasonable self-defence".
Mr Afzal, chief crown prosecutor for the north west, said: "It is difficult to envisage a more frightening set of circumstances than these."
He said Mr Coley was confronted by the men as he locked up his shop in Shrewsbury Street.
As they forced their way inside, Mr Coley was injured and his friend knocked unconscious.
At some point during the incident a gun - a blank-firing pistol - was discharged, Mr Afzal said.
He added: "All the evidence indicates that when Cecil Coley took hold of a knife that was on the shop counter and struck out with it he was acting in a way that he felt instinctively necessary to protect himself, whilst fearing for his life.
"It is clear from the evidence I have seen that Mr Coley was acting in reasonable self-defence, and used the degree of force that he believed was necessary when he fatally stabbed Gary Mullings and injured another of the intruders.
"I am therefore satisfied that there is insufficient evidence to prosecute Mr Coley."
The Crown Prosecution Service (CPS) said Mr Coley would not face any charges for injuring another intruder.
Ch Supt Mark Roberts, of Greater Manchester Police, said: "When presented with the circumstances of that evening the correct decision was to make the arrests. It was crucial that we conducted a thorough and open-minded investigation into the events.
"I am satisfied that we provided the full facts of the case to the CPS to enable them to make an appropriate decision."
Mr Afzal said householders, shopkeepers and "anyone going about their lawful day to day activities" would be protected by the law if they used reasonable force to protect themselves, their family or their property.
Three men - including two brothers of Mr Mullings - have been charged over the raid.
Kyle Mullings, 18, of no fixed abode; Joseph Junior Mullings, 24, of Anfield in Liverpool; and Nathan Walters, 25, of Thorn Court in Salford, have all be charged with robbery.
They are all due to appear before Manchester Minshull Street Crown Court on 13 October.