Three girls aged between 12 and 15 have been arrested following an alleged armed carjacking at Ingle Farm Shopping Centre in Adelaide, with police investigating the circumstances surrounding the incident.

According to South Australia Police, the incident allegedly occurred shortly before 3pm when a 61-year-old woman was approached and threatened with a knife. Police allege that her handbag and car keys were taken during the incident before the group left in her Nissan station wagon. The woman sustained minor injuries and was treated by paramedics.

The incident prompted a police investigation and search for the allegedly stolen vehicle. Officers later located the Nissan on Bridge Road, less than two hours after the alleged robbery.

Police say the vehicle was subsequently abandoned at Para Hills, where officers conducted a foot pursuit as part of their efforts to locate the people allegedly involved.

Three girls were arrested in connection with the investigation. A 15-year-old girl from Elizabeth East and a 12-year-old girl from Ingle Farm were charged with offences including illegal use of a motor vehicle and were granted bail.

A 13-year-old girl from Elizabeth South was also arrested. She was charged with a number of offences, including alleged assault, robbery and unlicensed driving.

Unlike the other two girls, the 13-year-old was refused bail and is due to appear in the Adelaide Youth Court.

Police recovered the Nissan station wagon and are examining the vehicle as part of their forensic investigation. Investigators are also continuing efforts to determine whether additional people were involved in the alleged incident.

The incident has drawn attention because of the young ages of the people arrested and the alleged use of a knife during the confrontation.

Carjacking and robbery investigations can involve several stages, including identifying suspects, recovering stolen property, examining forensic evidence and establishing the sequence of events through witness accounts and other available evidence.

For the woman involved, the incident resulted in minor physical injuries as well as the disruption caused by the alleged theft of her vehicle and personal belongings.

The recovery of the vehicle provides investigators with potentially important evidence. Police forensic specialists can examine a recovered vehicle for fingerprints, DNA and other material that may assist the investigation, subject to the evidence available.

The police investigation remains ongoing, and officers are continuing to establish the full circumstances of the alleged offence.

The case will now proceed through South Australia's youth justice system. Because the people charged are minors, additional legal protections apply to their identities and court proceedings.

It is important to note that the charges are allegations only. None of the accused people has been found guilty, and the matters will be determined through the court process.

The incident also highlights the importance of police investigations into offences involving vulnerable victims and alleged youth offending. Authorities will examine the evidence before determining whether additional charges should be laid.

The alleged carjacking occurred in Adelaide's northern suburbs, and the subsequent recovery of the vehicle at Para Hills formed an important part of the police response.

Police are continuing their investigation and may seek further information from witnesses who were present at Ingle Farm Shopping Centre or who observed the vehicle after the alleged incident.