An elderly couple are fighting for life after a violent confrontation at a rural property overnight left both of them with stab wounds and a man with a gunshot injury.

The incident happened shortly after midnight at a property 65kms south-west of Tenterfield.

Police say a 34-year-old man entered the home while a 75-year-old man and his 72-year-old wife were inside.

The woman suffered a stab wound to the chest and collapsed. Her husband received a serious wound to the abdomen.

The homeowner called Triple Zero for help as emergency services rushed to the scene.

Before police arrived, the 34-year-old man allegedly tried to get back into the house and was shot by the homeowner.

Paramedics treated all three people at the property.

The injured couple were airlifted to Gold Coast University Hospital in a critical condition.

The 34-year-old man was taken to Armidale Hospital under police guard.  He is reported to be in a serious but stable condition.

Detectives have established a crime scene and are investigating what led to the incident.

Police say early inquiries suggest the 34-year-old man was not known to the couple.