Elderly woman dies after 'horrific' three-car pile up in north-west Adelaide

An elderly woman has died following a three-car crash in Adelaide's north west. 

Emergency services were called the Port River Expressway at Gillman just after 7pm yesterday after reports a Mazda hatchback, a Nissan utility and a Mazda sedan had crashed. 

The 77-year-old driver of the hatchback was rushed to the Royal Adelaide Hospital but later died.

Her passenger, a 79-year-old woman from Glenside, remains in a serious but stable condition in hospital. 

The two drivers of the other vehicles were not seriously hurt.

Emergency services have described the crash scene as "horrific" with debris, glass and vehicle fragments strewn across the roadway for more than 100m.

Police are investigating whether one of the vehicles may have crossed over to the wrong side of the Port River Expressway causing the fatal crash. 

The freeway was closed eastbound for a number of hours while Major Crash investigators examined the scene but it has since been re-opened to traffic.