Steenkamp And Pistorius
Oscar Pistorius and former girlfriend Reeva Steenkamp.Reuters

Paralympic athlete Oscar Pistorius accessed pornography on his mobile phone the night he shot dead his model girlfriend Reeva Steenkamp, it has been alleged in the South African media.

According to documents leaked to the South African Times, the phone was retrieved from his Pretoria home, and suggests that he looked at the material while Steenkamp was present in the building, on Valentine's Day 2013.

The document goes on to state that this evidence paints a picture in "direct contrast to that of a loving couple spending their time together".

The South African Prosecuting Authority has refused to comment on the claims.

Pistorius, 27, shot his girlfriend four times through a locked bathroom door in his luxury home. He denies murdering her, claiming that he mistook her for an intruder.

On the anniversary of Steenkamp's death, he tweeted: "No words can adequately capture my feelings about the devastating accident that has caused such heartache for everyone who truly loved - and continues to love Reeva.

"The pain and sadness - especially for Reeva's parents, family and friends consumes me with sorrow. The loss of Reeva and the complete trauma of that day, I will carry with me for the rest of my life."

The reports follow claims from Pistorius's neighbours that they heard screams between gunfire on the night Steenkamp was killed.

In the court documents, one neighbour describes how the final gunshots "extinguished" the screams.

It is also claimed that a security guard on Pistorius's affluent estate called the athlete after hearing shots, but Pistorius told him everything was "fine".

Other documents show that a ballistics supports Pistorius's claim that he was not wearing his prosthetic limbs when he fired the shots.

Pistorius's trial is due to begin on 3 March.