There were two case of people impersonating police officers in the Table View and Milnerton areas in April.
Table View police spokeswoman Captain Adriana Chandler said three men, two wearing police uniforms, had got into a house in Arum Road, Table View, by posing as policemen.
But the would-be robbers fled empty-handed in a white car when the homeowner pressed a panic button.
Police arrested a man in Milnerton after he allegedly tried to bribe his neighbour while wearing a police uniform, which officers confiscated.
Milnerton cluster commander Major General Aneeqah Jordaan advised residents to demand appointment certificates from anyone in police uniform asking to enter their homes.
“If the officer cannot provide this card, do not allow them access to your home,” she said, adding that in some cases police uniforms were stolen off washing lines.