Pretoria, South Africa (CNN) -- Sounds of arguing for an hour before the shooting. Blood stains on a cell phone and cricket bat. Boxes of testosterone and needles.

The shape of prosecutors' case against Oscar Pistorius began to come into focus Wednesday as they argued the Olympian charged with killing his girlfriend, model Reeva Steenkamp, should be denied bail because he might disappear if released from jail.

But the Olympic sprinter's defense team battled back, questioning the quality of the police investigation.

The bail hearing ended Wednesday with no decision. Final arguments are scheduled for Thursday morning.

And all Steenkamp's family wants is the truth, her half-brother Adam told CNN's Jake Tapper on Wednesday.

Pistorius is charged with premeditated murder in the death of Steenkamp in the early hours of Valentine's Day. He has said he thought he was shooting at an intruder.

But police investigator Hilton Botha told the court Wednesday that Pistorius, 26, wasn't acting in self-defense when he shot through the door of a toilet room in the bathroom of his home and killed Steenkamp.

Botha said he believes Pistorius knew Steenkamp was on the other side of the door. He didn't explain why investigators think that but suggested Pistorius was specifically aiming to hit the toilet where Steenkamp had gone.

But he also said investigators have found no evidence that is inconsistent with Pistorius' story.

Pistorius' affidavit in alleged murder of girlfriend

Bail hearing

Prosecutors spent much of the hearing Wednesday focused on the bathroom of Pistorius' Pretoria home, where authorities say the track star shot Steenkamp three times, in the hip, elbow and ear.

Bullet trajectories show that Pistorius had to turn left and fire at an angle to aim at the toilet, Botha testified. Had he fired head-on into the door, he would have missed her, Botha said.

Defense attorney Barry Roux disputed that, saying the evidence does not show there was an effort to aim at the toilet.

Prosecutors are trying to prove Pistorius intentionally fired on Steenkamp, 29, in a premeditated attempt to kill her. Pistorius and his lawyers argue he mistook her for an intruder and killed her accidentally.

Pistorius said in a statement read Tuesday by his lawyer that he believes Steenkamp slipped into the bathroom when he got up to close the balcony door in his bedroom in the early hours of February 14.

Hearing noises and gripped with fear that someone had broken into his home, Pistorius said he grabbed his gun, yelled for the intruder to leave and shot through the toilet-room door before realizing the person inside might have been Steenkamp.

Roux said Wednesday that the defense team believes Steenkamp locked the door when she heard Pistorius yelling for the intruder to leave. He also said Steenkamp's bladder was empty, suggesting she had gone to the bathroom as Pistorius claimed.

Botha also said police believe a blood-stained cricket bat found in the bathroom was used to break down the locked door to the toilet.

Pistorius said in his statement that he used the bat to break down the door in an effort to get to Steenkamp to help her.

Botha agreed with the defense contention that, other than the bullet wounds, her body showed no sign of an assault or efforts to defend herself.

But prosecutors and Pistorius' defense battled over allegations that testosterone and needles were found at the home, as well as the quality of the police investigation.

Opinion: What my son taught me about Oscar Pistorius

Investigative errors?

Amid speculation by outsiders to the case that steroids or other drugs could have somehow played a role in the shooting, Botha testified that investigators found two boxes of testosterone and needles at Pistorius' home.

Under questioning by Roux, however, Botha said he hadn't read the full name of the substance -- which Roux said was an herbal remedy called testoconpasupium coenzyme -- when investigators took the materials into evidence. A quick Internet search on the name of the substance yielded no results.

He also said the defense forensics team found a bullet in the toilet that police had missed and noted police had failed to find out who owned ammunition found at the home or photograph it.

Investigators also went into Pistorius' home without wearing protective foot covers to prevent contamination of the crime scene, Roux said. Botha conceded that was true and said it was because police didn't have any more of the covers left.

Roux questioned police arguments that a witness heard sounds of an argument before the shooting. The witness, Roux said, lives 600 meters (more than a third of a mile) from Pistorius' home. Prosecutor Gerrie Nel countered that the witness lives 300 meters away.

Would he run?

Botha told Magistrate Desmond Nair that investigators believe Pistorius is violent and might flee if released from jail.

He described two encounters with Pistorius, one in which Botha said the track star asked someone else to take the blame when a gun went off at a Johannesburg restaurant.

Police said the second incident took place at a racetrack, where Pistorius allegedly threatened to assault someone.

Authorities have also said they have responded to previous domestic incidents at Pistorius' home, but have not elaborated.

In his statement Tuesday, Pistorius said he and Steenkamp were deeply in love and said he was "mortified" over her death.

High hurdle

Defense attorneys are trying to overcome South African law, which makes it difficult for defendants accused of premeditated murder to get out on bail. The law requires evidence of "exceptional circumstances" to justify release.

Nair upgraded the charge against Pistorius to premeditated murder Tuesday, saying he could not rule out the possibility that the track star planned Steenkamp's death. But Nair said he would consider downgrading the charge later.

In a statement read by his lawyer Tuesday, Pistorius said he would not try to flee or influence any witnesses if he is allowed out on bail, and he said his release wouldn't be a danger to public order.

Case rivets fans and friends alike

The case of the global sports hero known as the "Blade Runner" has riveted stunned fans around the world.

Social media reaction to the case appeared to come down against the sports star but was still noticeably mixed on CNN's Facebook page.

"There's no amount of tears that will save you," said Anthonia Nneka Nwabueze. "Pistorius must face the law for brutally killing an innocent girl -- Reeva."

"My favorite athlete but what he did is grave and must be punished," Carlos Alvarez Ochoa said.

But another person who posted called for patience.

"(N)one of us were in the house when his girlfriend was murdered, let's hold off on casting stones at Oscar Pistorius," said Adrian van Liere Since. "Just like anyone else, he deserves a just trial, and in my eyes remains innocent until proven guilty."

Coming to his defense were two acquaintances.

"I've never seen him show an angry side. I've never seen him lose his temper," Vanessa Haywood, a model and longtime friend, told CNN. "He's an incredibly kind and gentle human being."

Another endorsement came from a former girlfriend.

"I would just like to say, I have dated Oscar on off for 5 YEARS," Jenna Edkins said on Twitter. "NOT ONCE has he EVER lifted a finger to me, made me fear for my life."

In an interview for Wednesday's "Anderson Cooper 360," Adam Steenkamp told Jake Tapper "there was no indication that anything was bad. I mean, we know Reeva. We knew Reeva. She was happy. And if Reeva was happy, everything was OK... and everything was good, then everything was normal."

Steenkamp said he never spoke to his half-sister about Pistorius, and she didn't discuss the relationship much -- if at all -- with anyone in the family. So, without any in-depth knowledge, his family keeps vacillating about what the evidence suggests happened, he said.

"At a time like this, when people are grieving, I think it's hard to keep a clear mind on anything," Steenkamp said. "And with the added pressure and the media coverage and the interest, you know, from the world looking into this story, it's a rather unnatural situation. So, I suppose I would agree with everyone is flipping from one side to the other. We just don't know. You know, all that we want is we want to know what the truth is, and I think that's what everyone else would like as well. You know, to be able to make something of this -- to be able to deal with this and have something positive come out of this."

Steenkamp said the worst is over.

"We are all holding up very well considering the circumstances. We've now had just about a week to let things sink in. And we've had a very busy few days as well," he said. "I feel like we have done the most difficult thing for us as a family, so far, in viewing my sister's body, and then attending her memorial yesterday. We're doing OK."

CNN's Robyn Curnow and Kim Norgaard reported from South Africa, and Mike Pearson and Ed Payne reported and wrote from Atlanta. CNN's Nkepile Mabuse, Jake Tapper, Kara Kasarjian and Mark Morgenstein also contributed to this report.