The teenager accused of murdering Scottish tourist Karen Aim allegedly hid the baseball bat he used to kill her under his house and then showed the bloodstained, dented object to a man he knew.
Leigh Herewini, a 34-year-old security guard, said he felt "uncomfortable" when he saw the bat because "it could've been the bat that hurt the girl".
Mr Herewini was testifying at the second day of a depositions hearing at the Taupo Youth Court yesterday.
The accused, who was 14 when he allegedly murdered Ms Aim in January, stared at Mr Herewini while he gave evidence.
But Mr Herewini avoided his gaze and told the court the accused had shown him the baseball bat when he had gone to his house about two or three days after Ms Aim was killed.
"It had a lot of dents and bitsmissing off it," Mr Herewini said. "It looked like it had blood on it."
He said the accused had called him on the day Ms Aim was killed and told him he knew who was responsible for the murder.
"He said it was a guy Bryan, a Mongrel Mob prospect from Rotorua."
The accused allegedly said Bryan had hit Ms Aim over the head with a baseball bat and was planning on throwing her into the Waikato River "but there was too much traffic around so he left".
Ms Aim, 26, was on a working holiday and was killed while walking home after a night socialising with friends in Taupo. She was found lying in a pool of blood less than 100m from her flat.
Mr Herewini said the accused, who is now 15, told him he had tried to wash blood off the bat, and that he had found it on his back lawn after it was dumped there by "Bryan".
"I asked him if he thought this guy Bryan would turn himself in if he'd done this to the girl ... he said no."
The accused then allegedly put the bat back behind a small trapdoor under the house, where it was later found by police.
Mr Herewini was on security duty the night Ms Aim was killed and was called to Taupo Nui A Tia College when an alarm was activated by someone smashing windows.
Police allege the accused was responsible for the vandalism after CCTV footage showed a person riding a distinctive cruiser-style bicycle in the grounds, and Mr Herewini told police that the 15-year-old owned such a bike.
Under cross-examination, Mr Herewini denied an allegation by the accused's lawyer, Bill Lawson, that he would encourage young people to set off alarms so he could get extra money for security callouts.
He also denied that he and the accused would drive around and look at houses to potentially burgle.
Mr Herewini admitted that cannabis and "material suggesting possession of methamphetamine" had been found at his house.
During the afternoon, the prosecution called several forensic experts who testified that blood on the bat belonged to Ms Aim.
Ms Aim's underwear was torn when she was found, and although the experts found neither sperm nor saliva on her inner thighs or underwear, they said male DNA detected there was most likely that of the accused.
The hearing continues today.