SUDBURY – There was a heavy police presence in the Greater Sudbury Community of Garson Sunday afternoon.

Sudbury police say that a man was robbed at knifepoint outside a store with the suspect demanding prescription medication. 

Officers brought in the K-9 unit to conduct a dog track in the Penman Avenue area, but it was not successful.

Investigators say the suspect is black, in his mid 20's, and was wearing dark clothing. 

The investigation is ongoing.