The hearing continues Thursday in Pretoria with closing arguments from prosecution and defense, The Guardian reported. Prosecutors want Pistorius, 26, to remain behind bars while he awaits trial for killing Reeva Steenkamp.
Steenkamp, 29, a model and reality TV star, was locked in the bathroom of Pistorius' home in Pretoria when he shot her through the door. The defense says he believed an intruder had gotten in while prosecutors argue he shot her deliberately.
During the hearing, defense lawyer Barry Roux grilled Hilton Botha, the police officer leading the investigation. Botha was forced to concede that Steenkamp might have gone to the bathroom to use the toilet and not to hide from an angry Pistorius.
Botha also acknowledged that a woman who said she heard shouting between 2 a.m. and 3 a.m. could not positively identify the voices as Pistorius and Steenkamp.
On the issue of whether Pistorius is a flight risk, Botha said the prosecution arguments that Pistorius owns a home in Italy and has off-shore bank accounts are simply untrue.
Pistorius, charged with premeditated murder in the shooting death of Steenkamp, sat in the courtroom with his head bowed, sometimes crying, CNN said.
The hearing in some ways resembled a mini-trial, The Guardian said.
Botha testified Pistorius fired his gun directly at the toilet, saying if he shot at the door, he would have missed the toilet. He testified that he believed the athlete knew Steenkamp was in the bathroom when he opened fire.
Police recovered a firearm on a bathmat and two cell phones in the bathroom that weren't recently used. Botha said police believe a blood-splattered cricket bat found in the bathroom was used to break down the door.
Police said they found bullets in a safe and plan to add a possession of unlicensed ammunition charge against Pistorius, the police officer said. Two boxes of testosterone and needles also were found inside the home, officials said.
When cross-examined by defense attorney Barry Roux, Botha admitted police didn't try to determine who owned the ammunition, a live blog of court proceedings by The Guardian reported. Roux said the ammunition belonged to Pistorius' father.
"Did you take steps to find out who the owner of the ammunition was?" Roux asked.
"No, I didn't," Botha said.
Roux noted that a cellphone Pistorius used to call police was found elsewhere in the house.
Roux also said Botha has no evidence Pistorius attached his prosthetic legs before the shooting, which Botha admitted was the case. Prosecutors said Pistorius attached his prosthetics, walked about 20 feet to the bathroom and opened fire.
Roux said the substance Botha found in Pistorius' house wasn't testosterone but a herbal remedy, The Guardian reported.
"It's not a steroid and it's not a banned substance," Roux said.
Botha said he did not know the name of the substance, saying "didn't read the whole name."
Pistorius, a double-amputee who races on carbon-fiber blades, won two gold medals and a silver at the 2012 Paralympic Games in London. He was the first paralympic sprinter to participate in the able-bodied Summer Olympics in London.