The Pick n Pay Liquor Store in Walker Drive was robbed at about midday on Friday.
Police spokesperson Captain Sandra Janse van Rensburg said the teller and a co-worker sold airtime to one of the robbers, who was posing as a customer.
“He left and returned to the store with another man.
“The two then walked around the store before approaching the counter and pointing a firearm at the two tellers,” she said.
“The two men demanded money before they ran out of the store.
“It is thought that the suspects fled in a grey Nissan NP200 bakkie with tinted windows.”
On Thursday, a tavern in Sulo Street, Walmer township, was robbed by five men, who stole alcohol and money, Janse van Rensburg said.
“Later the same day, another business was robbed in Korsten, where the suspects took money and a vehicle.
“The vehicle was recovered abandoned in New Brighton.”
No-one was injured in any of the robberies.
Janse van Rensburg urged businesses to beef up their security.
She said they should also take note of people wandering around stores for extended periods without buying anything.