Pragaret Singh, father of three young children, was shot when he confronted robbers who attacked him after he closed his Manchester Food Traders store in the city for the night on October 31 last year.
The 35-year-old, known to friends and family as Charlie Singh, received gunshot wounds to his abdomen and chest and later died in hospital.
Three men, aged 22, 23 and 32, have been arrested on suspicion of murder and armed robbery, local Manchester Police said today.
According to investigators, Charlie's killers arrived in a light-coloured Seat Leon and after confronting and shooting Charlie, they got back in the car and drove off.
Charlie was robbed of 28,000 pounds from his shop's earnings on the day of the attack as he walked towards his BMW parked nearby.