Police are investigating the killing of up to 17 wallabies near Wodonga, in north-eastern Victoria.
The animals have been shot and killed over the past three weeks in the Stanley Forest, between Beechworth and Yackandandah.
Many of them had been decapitated.
Senior Constable Luke Millar says it is illegal to kill or shoot native wildlife and given the gentle nature of wallabies, it is an appalling act.
"They are not afraid of humans like a lot of other wildlife are," he said.
"They're a very gentle animal that usually just sits very close to the roadside and watch people go past.
"It would take a very disturbed person to get any enjoyment out of slaughtering poor defenceless wallabies."