An elderly couple have been critically injured and a man has been shot during a suspected home invasion in northern NSW.Emergency services were called to a rural property at Torrington, about 65 kilometres south-west of Tenterfield, just after midnight.Police have been told a 75-year-old man and 72-year-old woman were home when a 34-year-old man broke in and allegedly stabbed both with a knife.They say the woman collapsed with a chest wound, while her husband was slashed across his abdomen but managed to call Triple Zero (000).It will be alleged the younger man was shot by the resident as he attempted to get back into the house.The couple were treated at the scene by NSW Ambulance paramedics before being flown to Gold Coast Hospital in a critical condition.The younger man was treated at the scene for a gunshot wound and taken by road ambulance to Armidale Hospital under police guard.He is reported to be in a serious but stable condition.The 34-year-old has been charged with two counts of wounding a person for the intent of murder and is due to appear before a bail court hearing later today.Crime manager for the New England Police District, Detective Inspector Kingsley Chapman, said the incident took place on an isolated rural property."It's an extremely rare circumstance, it is very remote," he said."It was very confronting for both occupants who are in their 70s and have no doubt been in that community for many years and feel very safe in that community.Inspector Chapman said the man was also not known to police, but officers would be engaging with neighbours and the community as the investigation unfolded."First responders attended quite a traumatic scene, there's no doubt about that," he said.