Pinjarra family left devastated after stranger stabs dogs during walk

A Pinjarra family have been left devastated after their two pet dogs were stabbed during a morning walk.

Owner Marcus Norton was walking his dogs, Chief and Molly, at the off-leash exercise area on Carcoola Avenue last week when the pets approached a man who was also walking his dog.

Speaking to 9News Mr Norton said the man then stabbed his Mastiff puppy and elderly Staffordshire Terrier.

"Molly's harmless. She goes up and says hello," Norton told 9News.

" … Ok it might have been daunting there, you've got two dogs coming your way and you panicked.

"I was right there man, I was right there, I was talking to you, I was calling out to you,  just hang on."

Mr Norton's daughter Chevonne McNamara-Norton told 9News they carried the bleeding dogs to the car before rushing them to a vet.

"He cracked her skull, he punctured her lung, he stabbed her so deep on the back," Ms McNamara-Norton said.

Molly the Staffy suffered such serious injuries she had to be put down while Chief underwent surgery for his injuries.

WA Police said the dogs were stabbed with a "multi-use tool".

They also said the attacker's dog suffered bite marks.

9News contacted the accused for comment but he denied the request.

The investigation is ongoing.