Police followed a “trail of blood” up the stairs after being called to Oscar Pistorius’ house, a senior officer has told the athlete’s murder trial.
Col Schoombie van Rensburg said he found the South African Paralympian in a “very emotional state”.
Earlier, a forensics expert defended police handling of evidence.
Mr Pistorius denies murder, saying he shot his girlfriend Reeva Steenkamp on 14 February 2013 after mistaking her for an intruder.
The prosecution says he tried to beat down the door and then fired the gun.
‘Marks on door’
Col Rensburg, who was initially in charge of the crime scene, said he immediately gave orders for it to be secured.
The court was shown photographs of the crime scene, while Col Rensburg described a “trail of blood” up the stairs and spots of blood on chairs in the living room.
Defence lawyer Barry Roux said that pieces of the door pictured at the scene subsequently went missing, and that the door was improperly stored in a body bag.
Mr Roux also asked a forensic science expert, police colonel Johan Vermeulen, why he had failed to notice marks on the bottom of the door.
Mr Pistorius said in his statement at the start of the trial that he woke in the early hours and walked on his stumps to the balcony, pulled in two fans, closed the sliding door and drew curtains. He said that shortly before he had spoken to Reeva, who was in bed beside him.
He said he rejected prosecution claims that a witness heard arguing coming from the house before the shooting.
2. Bathroom noise
Mr Pistorius said he heard the bathroom window sliding open and believed that an intruder, or intruders, had entered the bathroom through a window which was not fitted with burglar bars.
“Unbeknown to me, Reeva must have gone to the toilet in the bathroom at the time I brought in the fans,” he said.
Mr Pistorius said he approached the bathroom armed with his firearm, to defend himself and his girlfriend, believing Ms Steenkamp was still in bed.
Both sides agree four bullets were fired. Ms Steenkamp was hit three times.
Mr Pistorius said he fired his weapon after hearing a noise in the toilet which he thought was the intruder coming out of the toilet to attack him and Ms Steenkamp.
He said he was in a fearful state, knowing he was on his stumps and unable to run away or properly defend himself.
Mr Pistorius said he rejected claims that he was on his prostheses when he shot at the door.
A witness told the trial she woke to hear a woman screaming and a man shouting for help. She said that after the screams she heard four shots.
At his bail hearing last year, Mr Pistorius said he went back to the bedroom after shooting at the toilet door, then noticed Ms Steenkamp was not in bed.
Mr Pistorius said he then realised she could have been in the toilet.
5. Toilet door
Mr Pistorius said he went back to the bathroom but the toilet was locked, so he returned to the bedroom, pulled on his prosthetic legs, turned on the lights before bashing in the toilet door with a cricket bat.
Forensics expert Johannes Vermeulen told the court that the height of the marks on the door caused by the cricket bat suggest Mr Pistorius was on his stumps at the time.
6. Emergency calls
Mr Pistorius’s defence team has said he then called security at the gated housing complex and a private paramedic service before carrying Ms Steenkamp downstairs.
But security guard Pieter Baba told the trial he had called Mr Pistorius first, in response to neighbours’ reports of gunfire, and not the other way round.
He said Mr Pistorius had told him: “Everything is fine,” before calling him back a few minutes later and crying down the phone.
The lawyer said that the marks were caused by Mr Pistorius trying to kick down the door using his prosthetic legs.
However, Col Vermeulen told the court in the South African capital Pretoria on Wednesday that the angle of marks on the door proved that Mr Pistorius was not wearing his prosthetic legs when he hit the door repeatedly with a cricket bat.
This contradicted testimony previously given by Mr Pistorius in which he said that he had put on his prosthetic legs before he attempted to break down the door with the bat.
Correspondents say whether or not the athlete was on his prosthetic limbs when breaking down the door is important because it could match parts of his story that he shot Ms Steenkamp accidentally, or expose inconsistencies in it.
The damaged toilet door, with four bullet holes, is in court along with a replica of the bathroom where Ms Steenkamp died.
Before Col Rensburg began his testimony, photographs of Ms Steenkamp’s bloodied head and face were shown in court, prompting Mr Pistorius to vomit.
He was sick several times on Monday while evidence from the post mortem examination was presented to court and has also cried on several occasions.
The trial, now in its ninth day, is expected to call on over 100 witnesses.
The state is seeking to convince the court that Mr Pistorius and Ms Steenkamp – a 29-year-old model, reality TV star and law graduate – had an argument before the athlete fired the shots that killed her.
There are no juries at trials in South Africa, and his fate will ultimately be decided by the judge, assisted by two assessors.
If found guilty, the 27-year-old, a national sporting hero dubbed the “blade runner”, could face life imprisonment.