The incident occurred inside the Mr Price store, at around 1pm, when guards were collecting cash from the store.
Police spokesperson Lieut Nomsa Sekele said the cash-in-transit guard noticed a suspicious-looking man in the store, but proceeded to the pick up room anyway.
When he came out of the cash office he saw the man again, and decided to change routes, but then another man, approaching from the front, pointed a firearm at him,” said Sekele.
The first man then came from behind and also pointed a firearm at the guard, and disarmed him.
“They then grabbed two boxes containing cash from the guard and told him to run,” said Sekele.
The two also left the store running.
Sekele said video footage from inside the store captured the incident.
No shots were fired and no one was injured in the robbery.
Police are investigating.
The Lakeside Mall had not yet commented at the time of going to press.