Two children are in a critical condition and the New England Highway at Whittingham is closed after a multi vehicle crash this morning.
Emergency services were called to the highway 500 metres north the Range Road intersection, 3 kilometres south of Singleton just after 11:15am following reports of a head-on crash between a car and a 4WD.
Two rescue helicopters are on their way to the scene and 11 NSW Ambulance paramedics are on the scene.
The female driver of the car and a child passenger are in a critical condition and are being treated at the scene.
The Westpac Rescue Helicopter has transported a 6 year-old-boy to John Hunter Hospital suffering multiple injuries and he is in a serious condition.
Two other children are also being treated for non-life-threatening injuries.
The male driver and sole occupant of the 4WD has been taken to John Hunter Hospital with non-life-threatening injuries.
There are significant traffic delays in the area, heavy vehicles are being urged to seek an alternate route.
Motorists are advised to avoid the area and consider using Putty Road and the Golden Highway instead.
Light vehicles already in the area are being diverted into Range Road.
Emergency services and traffic crews are on site working to free a trapped person.
The highway is expected to remain closed for some time.
Image credit: NBN News, Lauren Kemp