Warning: Graphic content.
Former flatmates of a man accused of murdering his ex-wife have described his fixation with her and how he talked about various ways of hurting her.
Manchao Li, 65, is on trial in the High Court at Auckland as he denies murdering Zhimin Yang, 57, and breaching a protection order.
The Crown alleges Li stabbed his former partner, also known as Jennifer, 12 times in a fatal attack in the West Auckland suburb of Massey in July last year.
Li's former flatmate Garrick Protheroe told the court the accused had said life would be better if Yang was no longer on the planet.
Protheroe said he had repeatedly advised against violence.
"Don't even entertain those thoughts because they are unhealthy and they are holding you back," he said.
"Your marriage is over."
Initially for a short time, it seemed like Li was taking heed of the advice, Protheroe said.
"But then he turned a corner and it was full on," he said.
His personality changed and he reverted back to the man he had initially been who had a fixation on "getting rid of the b***h".
"He showed me a number of rifles that he had. He showed me a hunting knife which he had bought. And a meat cleaver."
Protheroe said Li had a go at a tree in the back yard to see how the cleaver would work.
Li felt if he used that to disfigure his ex-partner then she would be reminded of him every day, what she had done and how he had repaid it, Protheroe said.
Li had also talked about wanting to burn her house down with her inside, the court heard.
Protheroe said Li, whose English was not as good as his own, also wanted help writing a letter to Yang's employer.
He was "fixated" with the fact she had this really good job at the library, he said, and felt if he wrote a letter saying she was evil she would get sacked.
Protheroe declined to help.
"Don't go down that path it's not worth it," he recalled telling Li.
Crown prosecutor Nick Webby asked if Protheroe had been concerned for his own wellbeing living in that house, and the latter replied he was confident he could look after himself.
"But in saying that of course you go to sleep at night and you never know what is going to happen. So I didn't feel comfortable, no."
Defence lawyer Sam Wimsett asked Protheroe if he knew about his client's mental health issues and that a nurse or social worker would visit.
"Somebody came to check on him occasionally, yeah," Protheroe said.
Wimsett also asked if Li was mad with the Ministry of Justice.
"He was mad with everybody," Protheroe said.
"Immigration," Wimsett added, "the courts."
"He would write letters to the Prime Minister, do you remember that?"
"I wasn't aware but that doesn't surprise me," Protheroe replied.
The other flatmate in the house, Theresa Bushell, also told the court about the cleaver, saying Li had once put his hand on the kitchen bench and said "chop chop".
Bushell recalled Li saying then his ex-wife would "not be able to steal from anyone else".
"He had it in his head she had stolen from him," Bushell said before adding it wasn't true.
She also told the court Li had "very little respect for women".
"The way he would treat me sometimes, like I just wasn't there."
In January 2018, Senior Constable Martyn Spear warned Yang of threats against her, after police were alerted by Li's support workers.
Spear told her she had grounds for a protection order and worked on a safety plan with her, the court heard.
When Spear later went to the defendant's home he very "strenuously" denied that the pair had been married.
Li was warned about the threats, the court heard.
After the protection order was served, Spear was involved in removing weapons from Li's home.
Li was asked to advise police if any weapons were on the premise, but he walked past them heading for his bedroom - an area he was being told not to go, Spear said.
"We weren't fast enough because he reached behind the door and grabbed hold of an air rifle."
Li was then restrained, he said.
Two air rifles were found, one had a silencer mounted on the end and the other had the barrel cut down to fashion it into a pistol, he said.
There also appeared to be a GPS tracking device, he said, and there were documents that seemed to show he had been making efforts to find Yang's address.
Bushell arrived and told Spear that Li was fixated on issues with his ex-wife.
"Did she say anything about how Mr Li intended to resolve those issues?" Webby asked.
She said he had described a method of how he would kill her - lighting an object and throwing it through a cat door of her home while she was sleeping at night, Spear said.
"I was very upset by it. I knew it was very important for me to warn Ms Yang as soon as possible.
"I drove directly to her workplace to warn her and to discuss further safety measures that would be needed."
The trial continues tomorrow.
Domestic violence - do you need help?
If you're in danger now:
• Phone the police on 111 or ask neighbours of friends to ring for you.
• Run outside and head for where there are other people.
• Scream for help so that your neighbours can hear you.
• Take the children with you.
• Don't stop to get anything else.
• If you are being abused, remember it's not your fault. Violence is never okay
Where to go for help or more information:
• Shine, free national helpline 9am- 11pm every day - 0508 744 633 www.2shine.org.nz
• Women's Refuge: Free national crisis line operates 24/7 - 0800 refuge or 0800 733 843 www.womensrefuge.org.nz
• Shakti: Providing specialist cultural services for African, Asian and middle eastern women and their children. Crisis line 24/7 0800 742 584
• It's Not Ok: Information line 0800 456 450 www.areyouok.org.nz