An elderly couple has sustained severe injuries, and a man has been shot during what is believed to be a home invasion in northern New South Wales.

Emergency responders were dispatched to a rural residence in Torrington, located approximately 65 kilometers southwest of Tenterfield, shortly after midnight.

According to police reports, a 75-year-old man and a 72-year-old woman were inside their home when a 34-year-old man allegedly broke in and attacked them with a knife.

Authorities state that the woman fell to the ground after suffering a stab wound to her chest, while her husband, who received a slash to his abdomen, was able to contact emergency services by dialing Triple Zero (000).

It is claimed that the younger man was shot by the homeowner as he attempted to re-enter the residence.

The couple received immediate medical attention from NSW Ambulance paramedics at the scene before being airlifted to Gold Coast Hospital in critical condition.

The younger man was treated on-site for his gunshot wound and subsequently transported by road ambulance to Armidale Hospital under police supervision. His condition is reported to be serious but stable.

A crime scene has been established, and police have indicated that initial investigations suggest the younger man was not acquainted with the elderly couple.