SA man pulls knife on bus passenger

A young man has allegedly pulled a knife on a passenger on an Adelaide bus.

The 20-year-old threatened the passenger and demanded his mobile phone in Gepps Cross on Thursday afternoon.

The victim refused and managed to get off the bus at the next stop while the suspect then changed buses.

A police dog was used to track down the young man, who's been charged with robbery, theft and unlawful possession and will face court on Friday.