Inspector Sello Mangena said the G4 security guard was accosted by an armed man while leaving the Soshspares store in Soshplaza on Wednesday afternoon.
"An unknown man cocked a firearm and instructed him to hand over the cash box he was holding to another man standing alongside them. The armed man then fired a shot and took the security guard's firearm," Mangena said.
Taking the cash box containing "a lot of thousands", the two men ran towards an Audi parked nearby where another armed man was waiting for them, he said.
The three men then fled the scene.
No one was injured in the incident and police were still searching for the trio.
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