Tragic teenage couple Reinhard Wallecker, 18, and Stefanie Tanzer, 17, had slipped into the garage at Wallecker's family home after finding his parents were in the house.

But as temperatures plummeted to -15C, Wallecker is believed to have turned the engine and heater on in his Mazda 323 to warm them up.

The tragic lovers were found the next morning when Tanzer's father dad battered down the door of the garage in Ternitz, Austria, after searching for his daughter.

He discovered the young couple suffering from carbon-monoxide poisoning and desperately tried to resuscitate the pair while waiting for an ambulance.

It is the second death of young lovers killed after parking their car and leaving the engine running to keep warm.