Oscar Pistorius has left prison in South Africa after serving just 12 months of a 5-year sentence for killing his girlfriend Reeva Steenkamp.

The Olympic and Paralympic athlete was released a day earlier than expected from Kgosi Mampuru II Correctional Centre in the South African capital of Pretoria. 

He will serve the rest of his sentence under house arrest.

Miss Steenkamp died when he fired four shots through a locked toilet door - claiming he thought she was an intruder.

Prosecutors have appealed the trial verdict of "culpable homicide" and will seek a murder conviction at South Africa's Supreme Court next month.

If Pistorius is convicted of murder he faces going back to prison for at least 15 years.