Police are investigating a mini-bus crash north of Coonabarabran on Monday morning in which eight people were injured, and which forced the closure of the Newell Highway for about seven hours.

About 7am on Monday a Hyundai Imax was travelling south on the Newell Highway, five kilometres north of Coonabarabran, when it veered off the road and struck a tree.

Multiple ambulances were dispatched to the scene, alongside a Westpac Rescue Helicopter medical team which was called to the scene shortly after 8am.

According to a release from the Westpac Rescue Helicopter service, some of the bus' passengers were trapped for a period of time.

One passenger, a 31-year-old female, was airlifted from the scene with serious spinal injuries.

A 24-year-old female was taken by road to Narrabri Hospital with spinal injuries.

The six remaining occupants, including four males and two females, were taken by road to Coonabarabran hospital.

Two of those, including a 10-year-old boy and a 60-year-old female, were subsequently airlifted to Orange Hospital with serious internal injuries.

The Newell Highway was closed until 2pm while investigations took place.

Crash Investigation Unit officers are conducting inquiries into the incident and are urging any witnesses to contact Crime Stoppers on 1800 333 000.

EARLIER:

A 31-YEAR-OLD female with suspected head and spinal injuries is being flown to Royal North Shore Hospital after an accident near Coonabarabran on Monday morning.

Shortly after 8am a call was received for the Westpac Rescue Helicopter's medical team to attend the scene of a single vehicle accident three kilometres north of the town where the vehicle had impacted a tree.

According to a release from the service eight people were on board the vehicle and some of the passengers were trapped for a period of time.

A female patient has also been taken by ambulance to Coonabarabran Hospital while a decision is still to be made on a 31-year-old male with suspected spinal injuries.

More information will be relayed once it is released.