An Australian man arrested for stealing a car while a 5-year-old boy was in the back seat says the child’s father should “realise his stupidity” for leaving his son unattended.

The bizarre sequence of events played out at a petrol station south-east of Melbourne, 9News reported.

A man left his ute running outside the Shell service station in the suburb of Officer while he went inside the store to buy a slab of water.

When he returned, his car and his son were gone.

CCTV showed what happened next.

A man on a motorbike had jumped into the car and driven off.

“The quick-thinking dad has called his own phone he left inside his vehicle which was answered by the alleged car thief,” a police spokesperson said.

“He alerted the male driver to the fact that his son was in the car and urged him to drop his son at a police station.

“The alleged offender has driven the boy to Pakenham Police Station where he was promptly arrested and the boy safely reunited with his father.”

But the man accused of theft tells a very different story, claiming he was the hero of the day.

“It’s not a big crime, right? I’m saving a child mate,” 42-year-old Duaraj Karishna Ramanujam told 9News.

He said the father should “realise his stupidity” for leaving his car running and claimed he was already on his way to the police station when he picked up the call from the panicked dad.

“What I did is the right thing to do. I’m using more common sense than anyone else,” Ramanujam said.

“My advice to them is to consider their action that led to these consequences.”

Police released Ramanujam after his arrest but he is yet to be formally interviewed and may still faces charges in relation to the incident.