Five people, 19, 18, 20, 19 and 23, hospitalised after car crashed into tree in St Kilda

The five young people hospitalised after a horror crash in St Kilda on Saturday have been identified, with police continuing to investigate the circumstances of the smash.

The five young people hospitalised after a horror crash in St Kilda on Saturday have been identified, with police continuing to investigate the circumstances of the smash.

About 5.20pm, emergency services were called to St Kilda Rd after reports a car had collided with a tree.

The driver of the car, a 19-year-old man from Smithfield, along with his four passengers were taken to hospital.

On Sunday morning, SA Police confirmed an 18-year-old Elizabeth Grove woman who was sitting in the front left passenger seat suffered serious injuries and remains in hospital in a critical condition.

A 20-year-old woman, 19-year-old man and 23-year-old man were also in the vehicle.

Five young people were hospitalised after a horror crash in St Kilda on Saturday. Picture: 7NEWS

Major crash officers attended the scene and investigations into the crash are ongoing.

The collision wrapped up a horror day on SA roads, with three people losing their lives in crashes across the state.

Just after 10.30am, a Ford station wagon and a Toyota ute collided on the Riddoch Highway, near Nangwarry in the South-East.

A Nangwarry woman, 59, who was driving the Ford, died at the scene.

Her passenger, a Mount Gambier woman, 68, was taken to hospital where she later died.

Just hours later, a Subaru station wagon and a Kawasaki motorcycle collided on Main South Rd, Wattle Flat, on the Fleurieu Peninsula, about 2.50pm.

The rider, an Aldinga Beach man, 55, died at the scene. The driver of the Subaru, a Glenalta man, 53, was not injured.

The current road toll is 89, compared to 112 at the same time last year.

Originally published as Five people, 19, 18, 20, 19 and 23, hospitalised after car crashed into tree in St Kilda