The incident took place on Saturday, 14th June.
The man is described as white with tanned skin. He is aged in his late 30s and is of medium build with short dark hair. He was wearing a white T-shirt with motif.
The woman is described as white of heavy build with shoulder length hair. Her hair is blonde at the front and dark at the back. She was wearing a brown top over a white vest.
If you recognise them or think you can help, please call the police on 101 or Crimestoppers on 0800 555111.