A South Australian police officer is facing an online backlash after he was filmed firing multiple gunshots at an injured kangaroo in an attempt to kill it.

Police were called to an oval at Stuart High School by a wildlife rescue group to put the animal down after it was noticed with a broken leg.

WARNING: Graphic images.

A South Australian police officer is at the centre of an online backlash after being filmed shooting an injured kangaroo multiple times in an attempt to put it down. (Supplied)

In the footage, the officer can be seen facing off with the kangaroo before aiming towards it and firing multiple rounds, despite it still standing.

Meanwhile, stunned onlookers can be heard in the video – which has been shared to social media and seen more than 10,000 times – asking why the process was taking so long.

“Oh my god man. Seriously, what’s that like – five rounds?” one witness said.

Officers were called to the oval of Stuart High School in Whyalla after being told the kangaroo had broken its leg. (Supplied)

In front of shocked onlookers, the officer was seen firing off up to five rounds at the animal, despite it still standing. (Supplied)

The RSPCA has since highlighted guidelines for putting animals down – with the recommendation of one single shot to an injured animal’s head.