South African athlete Oscar Pistorius was convicted of murder on Thursday as the Supreme Court of Appeal set aside the previous ruling of culpable homicide.

Pistorius, also often referred to as the 'blade runner', was found guilty of killing his girlfriend Reeva Steenkamp in February 2013.

The court said on Thursday that there were 'errors in law' in the previous conviction by the lower court. 

Pistorius was sentenced to five years last year for culpable homicide. He is currently under house arrest. 

The appeal court judge said that the star athlete "must have foreseen" that shooting at the bathroom door would have killed the person behind it. 

"Guilty of murder, with the accused having criminal intent," judge Eric Leach said, according to AFP. 

The Paralympic gold medallist now faces a maximum sentence of 15 years in prison for murder. 

The appeal court has referred the matter back to the trial court for an 'appropriate sentence'.