South Africa’s Supreme Court of appeal has overturned a manslaughter sentence on Olympic and Paralympics sprinter Oscar Pistorius to murder for shooting his girlfriend Reeva Steepkamp to death through a locked bathroom door.

A double amputee, Pistorius was sentenced to five years in prison in 2014 after being found guilty of manslaughter by a lower court and was placed under house arrest in October after serving a year in jail.

The athlete claimed he thought someone had broken into his house.

Judge Eric Leach said the manslaughter conviction, also known as culpable homicide, was based on a misinterpretation of the laws and an erroneous dismissal of circumstantial evidence.

“As a result of the error of laws referred to and on a proper appraisal of the facts, he ought to have been convicted not of culpable homicide on that count but of murder,” Leach said in his ruling.

Pistorius, 29,  who became famous internationally after competing for South Africa at the Olympics and Paralympics in London in 2012, will remain under house arrest awaiting another new sentence.

He was not present in the court during the appeal ruling.