Officers said the reported attack happened in the area of the Checkers Fuel Station on Georgetown Road around 13:30 on Friday (5 November).
They said the man had been travelling on his scooter in the direction of New Era when the alleged attack occurred.
Appealing for more information, they explained: “…As he passed the garage a large black or brown dog, being walked by a woman, has pulled on its lead, dragging the woman somewhat and has bitten the man on the left side of his chest.”
Anyone who saw what happened is urged to call Police on 612612 or make an anonymous report using Crimestoppers’ online form.