The owner had just put her child in the back seat when a man pulled up in a stolen Mazda utility and switched cars.
"It appears to be random at this stage," Senior Constable Gen Cullinan told ABC Radio Adelaide.
"It would appear they've dumped one car and then literally tried to take another car so there's no indication these people are known to each other."
- Snr Con Cullinan
The stolen Honda was last seen heading towards Windsor Grove, at the eastern end of Fourth Avenue.
The man has been described as Caucasian, aged in his mid-20s, with dark hair.
Police have asked anyone who sees the Honda Jazz to call 131 444.
More to come.
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