oscar pistorius
State has filed appeal against Oscar Pistorius' conviction and sentenceReuters

Oscar Pistorius faces the possibility of a much longer prison sentence after prosecutors launched an appeal against his conviction and punishment for killing his girlfriend.

South Africa's National Prosecuting Authority (NPA) has filed an appeal, it was announced on Tuesday morning (4 November).

A NPA spokesman said: "Today, we announce that the NPA filed the application for leave to appeal both the conviction and sentence. The appeal on conviction is based on the question of law."

No date for the appeal hearing has been set.

Pistorius, 27, was convicted of culpable homicide and not murder in the shooting of Reeva Steenkamp on Valentine's Day, last year.

The appeal is likely to seek to convict the fallen track star of murder, after prosecutor Gerrie Nel sought to prove at trial that Pistorius deliberately shot dead Steenkamp in a hail of gunfire at his luxury home in Pretoria.

Pistorius was jailed for five years by judge Thokozile Masipa, in a sentence condemned as too 'soft' by a large section of public opinion in South Africa.

Judge Masipa said in her judgment that the facts were not available to convicted the Bladerunner of premeditated murder.

Pistorius' family have said previously he accepted the sentence and did not intend to appeal. The former athlete has always denied killing Steenkamp deliberately, claiming he acted in a misguided bid to protect her from a supposed intruder.