A female patient was at Westmead Hospital in a stable condition, a spokesperson for Western Sydney Local Health District said on Thursday.

Emergency services were called to the scene along the Mitchell Highway about 30km west of the town about 5.30am Wednesday.

The female driver died at the scene, and three passengers were treated by paramedics for various injuries and airlifted to Sydney, police said.

WEDNESDAY:

Police have confirmed a woman has died in a crash near Nyngan on Wednesday morning.

Another three people sustained injuries and have been airlifted to a Sydney hospital.

About 5.30am on Wednesday, emergency services were called to the Mitchell Highway, about 30km west of Nyngan, after a vehicle left the road and crashed into a tree.

The female driver died at the scene, police said at 10.30am.

Three passengers were treated by NSW Ambulance paramedics for various injuries.

They have been airlifted to Westmead Hospital in various conditions, police said.

Officers attached to Central North Police District established a crime scene, which is still being examined.

An investigation into the circumstances surrounding the crash is under way.

As inquiries continue, police are appealing to any witnesses to the crash or anyone who might have dashcam footage to come forward.

The road was reopened and traffic conditions were returned to normal at 4pm.

ALSO MAKING NEWS:

EARLIER:

Emergency services remain on scene of a serious crash north of Nyngan at Girilambone on Wednesday morning.

A helicopter has been called to the scene to transport patients from the vehicles.

More to come.

UPDATED 10am:

The Mitchell Highway has reopened under stop/slow traffic conditions at Girilambone, north of Nyngan, following a serious crash near Arcturus Street/Murrawombie Road.

Both directions had earlier been closed as a result of the crash.

Motorists should continue to allow extra travel time, with traffic slow past the scene.

Emergency services and traffic crews remain on site.

READ ALSO:

EARLIER 7.30am:

The Mitchell Highway is closed in both directions at Girilambone, north of Nyngan, due to a serious crash near Arcturus Street/Murrawombie Road.

Southbound traffic on the Mitchell Highway is being diverted via Railway Road, Yarrandale Road and the Barrier Highway.

Northbound traffic should divert at Nyngan via the Barrier Highway, then use Yarrandale Road and Railway Road to return to the Mitchell Highway.

This diversion will add about 30 minutes additional travel time and is suitable for all vehicles.

Motorists should allow extra travel time and follow the directions of emergency services and traffic crews on the scene.

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