A 21-year-old man has been charged after allegedly threatening a Facebook Marketplace phone seller with a knife, forcing him into a car and assaulting him in Kaleen.

Police say the victim went to a Kaleen address about 5.30pm on Tuesday to sell a phone after arranging the transaction online.

An unknown man examined the phone before the 21-year-old allegedly emerged from a nearby Volkswagen Golf and threatened the seller with a knife.

He allegedly forced the victim into the car, punched and strangled him.

The victim managed to escape and call for help before the Golf was driven away.

Police spotted the Golf in Belconnen on Thursday afternoon and stopped it on Cohen Street, where they arrested the driver.

The 21-year-old has been charged with forcible confinement, assault occasioning actual bodily harm, possessing an offensive weapon with intent and committing an act that endangers health by choking, suffocating or strangling another person.

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