The victim was identified as Hunny, who jointly runs the shop with his brother Sunny, who was also present during the incident.
The traders' family alleged foul play accusing their neighbour, Jonu, of leaving the pistol on the table of the shop with malafide intentions.
"Jonu requested us to keep a polythene bag with something inside it at our shop for few minutes and left in a rush. Minutes later Avadesh came and started fiddling with it," Sunny told police.
Police have arrested both Jonu, who had kept the bag, and Avadesh, who allegedly accidentally fired the shot, and registered a case under the Arms Act.