Judge Thokozile Masipa has told the High Court in Pretoria that she has disregarded the evidence provided by two of the state's witnesses while delivering her verdict in the murder trial of Oscar Pistorius.

During the six-month trial, Michelle Burger told the court that she heard "terrible screams" from a woman and four gunshots in the early hours of February 14 last year when Pistorius shot dead his girlfriend Reeva Steenkamp.

Ms Burger and her husband, who lived near to the Paralympian's home where the shooting took place, both gave evidence in the court, but were criticised by the defence for giving very similar statements.

Today, Judge Masipa told the court that the witnesses' evidence must be rejected because it was "unreliable", but she insisted that the pair were unfairly criticised for having almost identical statements.

The judge went on to say that the couple were "genuinely mistaken" in what they heard, and that some witnesses mistook gunshots for a cricket bat hitting the toilet door behind which Steenkamp was shot.

Pistorius has claimed that he broke down the toilet door with a cricket bat after firing the shots at who he believed was an intruder in his home.

The six-time Paralympic gold medallist denies murder.