In the film The Godfather, mafia boss Don Corleone has a severed horse’s head put in an enemy’s bed, but no one is sure what to make of the dumping of a dead koala with $50 in its mouth at a Victorian police station.

Sergeant Jason Von Tunk thought he was being set up for a possible ambush when he made the grisly discovery in the driveway of Heywood police station on Saturday night.

He heard a thud and went outside the station to investigate.

“I put my torch on it, and I saw it was a koala,” Von Tunk told Fairfax radio on Tuesday. “It made me shiver, I thought what’s this about, and I thought I was getting set up – the old put a dead koala out in the middle of the driveway situation, and then get ambushed. All sorts of things go through your head.”

His curiosity was piqued when he noticed there was $50 rolled up in the koala’s mouth, and police remain baffled about the motive behind the money.

“We don’t know what the message is,” Von Tunk said. “Why $50, I don’t know. I’m at a loss to explain why this happened.”

There was no evidence of cruelty but the koala had a head injury and looked as though it might have been hit by a car, he added.

The koala has since been buried and the money logged in a property book.