SA Police Superintendent Selena Dinning told reporters a short time ago that the woman’s three and eight-year-old sons sustained “a number of stab wounds”, but they are currently in a stable condition at the Women’s and Children’s Hospital.

She said the eldest son had already had surgery and is expected to make a full recovery.

The youngest child is due to have surgery later today.

Police arrested their 35-year-old mother from Modbury Heights last night after she allegedly stopped her silver Honda sedan on the North South Motorway at Wingfield – about 300 metres south of the Port River Expressway – and took her two sons out before stabbing them with a knife.

Dinning said a passing driver stopped to disarm the mother and shortly afterwards other members of the public assisted him to restrain the woman.

Police arrived at the scene shortly before 11.30pm.

“We are extremely grateful to the person that stopped and rendered assistance intervening in this incident, as no doubt the situation would have been much worse had they not stopped” Dinning said.

“It (the scene) quite frankly was horrific.

“Police officers are very resilient but we’re also very mindful of the fact that not only for police officers but also emergency service responders and also members of the public to be confronted with an incident like this is very significant.”

#Breaking: A woman has been arrested after allegedly stabbing her two children in her car at Wingfield last night.

Police will allege the woman, 35, stopped her car on the North South Motorway at Wingfield and removed her two young children before stabbing them with a knife. pic.twitter.com/x0IU0QeCqz

— 10 News First Adelaide (@10NewsFirstAdl) August 15, 2022

The woman was arrested and taken to Royal Adelaide Hospital last night, where she has been detained and will undergo a health assessment before police continue interviewing her.

Dinning said she would likely be charged with two counts of attempted murder and it was anticipated that she would have a bedside hearing later today.

She said police did not know what triggered the incident or to where the woman was driving.

SA Police is in discussions with the Department for Child Protection following the incident.

“We do have close relatives and yes, there is a father, but we will be having discussions with DCP about the ongoing care of those children,” Dinning said.

“From my personal perspective, the expressway incident is the first that I became aware of this particular family, but all of that history will be brought forward before the court.”

The incident is under investigation by Western District Detectives, who are calling any witnesses to contact Crime Stoppers on 1800 333 000.