Three men are being sought after the attempted theft of an eight-year-old Labrador from its owner.
E-fits of the men have been released by Cardiff detectives after the men, one armed with a craft knife, attempted the robbery.
The contents of a dog poo bag split over one of the suspects as the owner fought them off in Pentwyn, Cardiff, last month.
The 30-year-old dog owner suffered facial injuries and concussion.
He is recovering well at home with his two dogs who are also safe and well.
A member of the public stopped to help and called police after the attempted robbery at lunchtime on 25 February on a wooded trail between Eastern Avenue and the Rumney River near Pentwyn.
It is believed the suspects walked through Pentwyn and Llanrumney before and after the attempted robbery.
Det Con Kirsty Matthews said: "The victim was extremely brave and it is fortunate that he was not more seriously hurt as he did everything he could to stop the men from taking his dog.
"This is an isolated incident and extensive enquiries are being carried out to identify and arrest those responsible."
The force said it wanted to reassure the public dog theft numbers are very low.