The massacre of dozens of Kangaroo children occurred in the southeastern coastal town of Merimbula.
New South Wales state police said on September 30 that they believe the animals were run over by a vehicle at around midnight on September 28.
"The police are searching for witnesses to some of the animal cruelty that occurred in the southern coastal area of the state over the weekend," a police spokesperson said.
The agency in charge of national parks and wildlife is also participating in the investigation.
At least three young Kangaroo trees have been rescued from their mother's Kangaroo pocket and are being cared for and provided with educational, rescue and wildlife information at wires by volunteers.
Ms Janine Green, a volunteer at wires who discovered the Kangaroo, accused the perpetrator of driving a white car and turning on a headlight to deliberately run over the Kangaroo.
"They drove around, around and turned on the lights. So the Kangaroo just watched and stood there," Green told Guardian Australia.
"People here really love Kangaroo. They are part of the complex. Everyone woke up and recognized the bodies of the animals on their home grass. They couldn't believe it," she said.
