Lawyers for South African "Blade Runner" Oscar Pistorius poked holes in the prosecution's murder case against him Wednesday, challenging flawed police work to boost the athlete's hopes of being released on bail.

The defence forced the lead police investigator to admit multiple police errors in the case, undermining earlier explosive claims that witnesses heard arguing, a woman screaming and gunfire at his Pretoria home on Valentine's Day.

The 26-year-old Olympic athlete insists he shot dead Reeva Steenkamp, 29, in a horrible accident and not intentionally, as the prosecution aims to prove.

Under cross-examination, investigating officer Hilton Botha was forced to admit that Pistorius's version of the early morning shooting last Thursday fitted the crime scene.

"It sounds consistent," Botha said.

Defence lawyer Barry Roux went on to cast doubt on key witnesses at the bail hearing.

A woman who lives in the same highly secured complex as Pistorius "heard talking that sounded like non-stop fighting from two to three in the morning," hours before she was killed, Prosecutor Gerrie Nel said.

Another witness reported hearing gunshots, screams and then more shots, police said.

"We have the statement of a person who said after he heard gunshots, he went to his balcony and saw the light was on. Then he heard a female screaming two, three times, then more gunshots," Botha said.

But Roux disputed these accounts as police said one witness was at least 300 metres (nearly 990 feet) from the house and the other had misheard the number of gunshots fired.

Botha was also forced to admit police had missed a bullet that hit the toilet basin in their investigation. The defence's forensic team discovered the bullet four days later.

He also conceded he did not wear protective clothing when Pistorius's forensic team visited the house, which may have contaminated the scene.

In another twist, prosecutors late on Wednesday backtracked on the claim that a police search of Pistorius's home found testosterone and needles in a dresser in his bedroom.

"We can't tell what it is," said national prosecuting authority spokesman Medupe Simasiku later said. "We can't confirm or deny it until we get the forensic report."

Pistorius's defence team and his relatives looked confident at the end of the session, while prosecution's lawyers were seen to be holding worried discussions.

"The Pistorius family finds the contradictions in Botha's testimony extremely concerning," they said in a statement, adding that they were "satisfied" with the bail hearing.

Pistorius, the first double amputee to compete against able-bodied athletes in the Olympics in London last year, says he shot Steenkamp by mistake through a locked bathroom door, believing she was a burglar.

"I had no intention to kill my girlfriend," he said in an affidavit read to the court on the first day of his bail hearing Monday.

Steenkamp was shot three times through the bathroom door early on February 14, with wounds to her head, elbow and hip.

Although it appeared to be a successful day in court for the defence, Pistorius still needs to convince the magistrate there are compelling reasons why he should be let free during his trial.

Police revealed that Pistorius had previously been arrested at his Pretoria home for assault, although he was not charged.

Magistrate Desmond Nair said earlier he could not rule out that there was some planning involved in the killing, which may be considered as a premeditated murder, setting a high bar for bail.

The bail hearing was adjourned until Thursday when both sides are expected to summarise their arguments.

The athlete, who off the track has had a rocky private life with stories of rash behaviour, beautiful women, guns and fast cars, has built up a powerful team of lawyers, medical specialists and public relations experts for his defence.

In 2009, Pistorius admitted to a newspaper that he slept with a pistol, machine gun, cricket bat and baseball bat for fear of burglars.

He runs on carbon-fibre blades, which inspired his nickname, after being born without the fibulas in both of his legs which were amputated below the knee when he was a baby.

Pistorius revealed he earned 5.6 million rand ($640,000) a year and owned the $570,000 house where the killing took place as well as two other homes.

His career has been put on hold since the shooting, forcing him to cancel races in Australia, Brazil, Britain and the United States between March and May.

Two of his American sponsors, Nike and sunglasses maker Oakley, announced they were dropping Pistorius from their advertising campaigns, which have earned him millions of dollars in endorsements.

French cosmetics firm Clarins said Wednesday it was suspending a fragrance advertising campaign featuring Pistorius.