Police have arrested two boys, aged 10 and 16, and a 13-year-old girl after a string of violent attacks in Adelaide including the bashing of an elderly couple.

The gang of youths, described as being Aboriginal in appearance, allegedly attacked and abused an elderly couple after climbing on the roof of their Hackham West home early on Sunday morning.

CCTV footage shows the horrific moment a grandmother was kicked in the face by one of the attackers, while the couple were also spat at and slashed with a knife.

According to Seven News, the innocent couple were also allegedly called 'white invaders' and 'dogs' by the children.

A grandmother was allegedly attacked by a gang of youths who sliced her finger open and called her and her partner 'white invaders'

Police have arrested two boys, aged 10 and 16, and a 13-year-old girl after a string of violent attacks in Adelaide (CCTV of alleged attack on elderly couple pictured)

The alleged crime spree stretched across a number of suburbs, and is believed to have started after a man was bashed and had rocks and sticks pelted at his car in Adelaide's south.

The assault on Columbia Street at Morphett Vale just before midnight on Saturday was one of three incidents that police believe may be linked.

The man suffered facial injuries in the assault, which happened after he pulled over when rocks were thrown at his car.

Police say he was set upon when he approached a group of young people, while his car was substantially damaged before the group of youths ran away.

An ambulance transported the man to the Noarlunga Hospital for treatment.

A man was also attacked with a garden stake (pictured), according to police

The next incident came shortly after midnight when a car travelling on the Southern Expressway at Noarlunga Centre drove over some concrete.

The driver stopped to check his car and when he got out of the vehicle he had rocks thrown at him from an overhead bridge. The man was not injured and the car had minor damage.

Then just after 12.30am on Sunday two Hackham West residents reported having youths on the roof of their house to police.

The two residents were assaulted after they confronted the group and needed medical treatment at Noarlunga Hospital.

Police believe all incidents are connected and have been looking for four male youths and one female.

At 12.30pm on Sunday the trio were arrested at a Hackham West home and are expected to be charged with aggravated assault causing harm, aggravated assault and affray.

Investigations are ongoing and further arrests are likely.

CCTV footage shows a woman being shoved after a gang of youths allegedly were on the roof of her home

The attack follows two similar incidents in Adelaide's southern suburbs in March with police warning there is the potential for someone to get killed.

Social media users in the area reacted with anger on Sunday morning, fearing for their safety.

'To anyone who may be driving down the Southern Expressway, please be cautious as those idiots throwing rocks off the bridge are at it again…', one person said.

Another Facebook user posted to his local MP's Facebook page asking for help: 'I and my family do not want me to be injured or killed with this stupid and senseless stupidity.'

Investigations are ongoing and further arrests are likely.