Two elderly residents in the Pentlepoir and Saundersfoot areas are alleged to have been the subjects of deception.
During the last two weeks, a male person called at their homes and falsely deceived them into believing that their tarmac drives were in need of repair.
"Both people paid a sum of money to have the repairs done, but on inspection it was apparent that a substance similar to waste oil had been used during the process," explained a police spokesman.
Police are now anxious to trace the male person concerned, who is described as being approximately 60 years of age, five-foot eight inches tall and of medium build. He was also in possession of a Vauxhall Cavalier car.
If any member of the public is approached by this individual or offered similar services, they are asked to contact their local police station or local trading standards office.