Footage of a kangaroo that was run down by a vehicle and then tortured with a cigarette before having its head stomped off is being investigated by RSPCA South Australia.

It is believed the "barbaric" act of animal cruelty took place in South Australia on the evening of June 10.

RSPCA SA Chief Inspector Andrea Lewis said it was sent screen grabs from a series of 10-second videos posted to the Snapchat social media platform.

"I've been doing this job for 12 years and I've seen some pretty horrible things and this certainly rates up there with one of the worst things I've seen," she said.

"These images contain short videos of the animal being hit by a car and then a group of males stabbing the animal with a hunting knife in the head, and then burning its eye with a cigarette while it was allegedly still alive.

The kangaroo was hit with a vehicle before being beaten to death. ( Supplied: RSPCA )

"Once the animal had allegedly passed away, they've stomped on its head until its head came off its body."

The RSPCA said a 17-year-old from Adelaide's southern suburbs had been interviewed and inspectors were seeking additional information from the public.

"Anyone who witnessed the incident, has viewed the video or has copies or screenshots of the video, or has any additional information, is asked to contact the RSPCA South Australia's 24-hour cruelty hotline on 1300 477 722," Ms Lewis said.

Penalties for aggravated animal cruelty under the Animal Welfare Act include up to four years' jail or a fine of up to $50,000.