The suspect, who was about 1.85m tall, pointed a gun at her and demanded cash.
According to Springs police spokesman Capt Johannes Ramphora the woman pointed to a suitcase where she kept cash.
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Ramphora says the suspect took two suitcases and a bag full of clothing.
The woman’s friend and her brother were woken by the noise and the suspect also pointed the gun at them.
Ramphora says the man locked the three victims in the bedroom and took off with R15 000 in cash, a laptop, TV, tablet, clothing and two cellphones.
The victims waited until they thought it was quiet before they broke the bedroom door open to call for help.
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No arrests have been made.