The victim, identified as Rakesh Kumar Jain, was returning home on his two-wheeler when the two accused, who were following him, stopped him and asked him to give the keys of the cash box of his daily earnings, the official said.
Mr Jain was involved in the business of exchange of old notes.
He refused to give them the keys and they fired at him, the police official said. The bullet hit him in the chest.
The victim was rushed to the GTB Hospital, where he was declared brought dead, they said.
The victim had been attacked and robbed earlier also and the police are probing whether those men who were arrested earlier were involved in this incident.