A suspected armed robber stabbed to death during a bungled raid was cleared of murder nine years ago, police sources have confirmed.
It is understood that Gary Mullings, 30, was part of an armed gang which tried to rob a florists in Manchester.
He suffered fatal stab wounds during the incident.
Shopkeeper Cecil Coley, 72, has been arrested on suspicion of murder.
The Manchester Evening News said today that Gary Mullings was acquitted in January 2002 of the murder of Alan Byron, 18, who was shot dead in a car in Longsight a year earlier. Another man was convicted and jailed for life.
Police were called to the florist in Shrewsbury Street, Old Trafford, on Tuesday evening after reports that a man had been injured.
Police said a number of men had attempted to rob the shop and that a gun had been found at the scene.
Mullings was taken to hospital with a stab wound but died a short time later.
Mr Coley was also injured in the incident and was in hospital overnight.
Police said they expected to speak to him today.
A spokesman for Greater Manchester Police said a 19-year-old man who presented himself at Manchester Royal Infirmary with stab wounds on Tuesday had been arrested on suspicion of robbery.
Mr Coley's nephew, Glen Simms, 49, said his uncle had had the shop premises for 40 years.
Mr Simms said: "I heard that two men went in to rob the shop and that my uncle was there with a friend.
"It appears they were attacked and my uncle acted to defend himself."
Shauna Smith, 17, said Mr Coley was known as "Pudding" because he used to make "slushies" - crushed ice drinks - and described him as a "very nice and lovely man".
Other neighbours said drug dealing was known to go on in the area.