Police have been left frustrated after an investigation into potential human remains in WA's Pilbara revealed they were cow bones stuffed in a jumper.
WARNING: This story contains images that readers may find distressing.
A walker found what initially appeared to be a dead person on the side of a track in Wickham last week and reported it to police.
Roebourne Police Senior Sergeant Dale Harmer said the area was declared a crime scene while they studied the remains.
"With the assistance of our local forensic officers and the forensic pathologist in Perth, [we] identified the remains there to actually be of an animal," he said.
"The remains were stuffed inside a tracksuit to make it look like it was human remains.
"[It] has caused police to use an entire day and three police officers guarding a scene for something which was never a human in the first place."
Senior Sergeant Harmer said police attending the scene had thought the situation did not "look right", but they still had to follow protocol.
"You can't just go into looking at something like that and lifting it up and digging around it to see if it's human remains or animal remains, we need the right people up here to do that," he said.
"They do have to err on the side of caution and get the right people in, every time."
Forensic police from Karratha were pulled from other jobs to investigate.
Senior Sergeant Harmer said it was a waste of police time and tax payer dollars and impacted their ability to serve the community in a region where resources were already limited.