Police are hunting for a teenager they believe committed a series of armed robberies in Melbourne's south-east.

Five women, in four separate incidents, have been accosted and threatened with a knife by a young man in Hallam between the 5th and the 29th of August.

Police have appealed for any information that could help them catch this teen. Credit:Victoria Police

Police have set up an information caravan Sunday morning at Gunns Road reserve where many of the incidents took place, as they search for information that may help them identify the teen.

The boy is estimated to be around 15 years old and is African in appearance. He has a skinny build and short dark hair.