A South African appeals court overturned an earlier manslaughter verdict and found Oscar Pistorius guilty of murder on Thursday. The double-amputee Olympic athlete was convicted last year of culpable homicide for killing girlfriend Reeva Steenkamp in February 2013, after shooting her four times through a locked door. Justice Eric Leach overruled the decision, ruling that there was “fundamental error” with the judgment. Leach said Pistorius, who claimed he thought his girlfriend was an intruder, never offered an acceptable explanation for shooting Steenkamp. “I have no doubt that in firing the fatal shots the accused must have foreseen that whoever was behind door might die,” the judge said. The Olympian is under house arrest after spending a year of his five-year sentence in prison, but will return to court for a new sentence.