After she learned Wiremu Arapo had died as his home went up in flames, his fiance had a question.

Why couldn’t his friend and flatmate have saved him, given they had escaped relatively unscathed?

That was because they had beaten Arapo to death and set fire to the home in a futile attempt to conceal evidence of the murder, the Crown alleges.

Childhood friends Sean Hayde and Gregory Hart are on trial in the High Court at Auckland charged with the 27-year-old’s murder and perverting the course of justice by setting the home alight.

Hayde, who was once Arapo’s friend and boxing pupil, is also charged with assaulting, strangling and threatening to kill his former girlfriend in the weeks before the alleged killing.

Hayde and Hart deny all charges and are pointing the figure at each other.

Each will claim the other is solely responsible for killing Arapo, a former soldier remembered as a popular personal trainer with much to look forward to.

Crown prosecutor Ned Fletcher said the killing was driven by a tangled web of deteriorating relationships and infidelities, with the first eruption of violence being Hayde’s alleged assault of his former partner.

Hayde also resented Arapo’s continuing closeness with his new flame, as well as the personal trainer’s treatment of Hart, the jury heard.

Arapo had also grown increasingly frustrated with his flatmate Hart.

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Gregory Hart in the dock on the first day of his murder trial. Photo / Jason Oxenham

He was frequently behind in the rent and bills and failed to pull his weight and Arapo was in the process of kicking him out.

Before the alleged murder, Hayde had urged Hart to move out and said as soon as he had his bond back, he planned to “kick his [Arapo’s] teeth out”, the jury heard.

Hart seemed to resent being repeatedly told to clean up his act by Arapo. In a text message to Hayde 20 days before the alleged murder he wrote: “I’ll move in; n***** boy just had another one of his bullshit chats to me after u left”.

The resentments reached their crescendo on the evening of October 20, 2020, when Hayde and Hart drove around intending, at the very least, to give Arapo a serious beating, Fletcher said.

Today, the Crown called Mohammed Muzammil, one of Arapo’s closest friends, as a witness.

They met at a gym where Arapo was a personal trainer and the pair understood each other from day one, Muzammil said.

In 2020, he would visit the Minerva Tce rental where Arapo had set up a gym for personal training sessions.

He was at the home on the afternoon of October 20 and was one of the last people to see Arapo alive.

Muzammil said he saw Arapo light a candle that afternoon. He had done a spring clean and wanted the rental to smell good for his fiance, who had recently enlisted in the Navy and who was set to return to the property for a visit after training at Devonport.

The candle came up again during his brief cross-examination by Hayde’s lawyer Julie-Anne Kincade KC.

Part of Hayde’s defence will be that the fire could have been caused by the candle accidentally tipping over.

Sean Hayde is accused of domestic violence against his former partner, along with the murder of Wiremu Arapo. Photo / Jason Oxenham

The day after the fire, Muzammil said he spoke to Hart on the phone.

He alleged Hart said: “I am still in shock, I feel like I failed Wiremu”.

Hart also told him he was outside having a cigarette while Hayde and Arapo were inside drinking wine and playing PlayStation.

Muzammil said he told Hart that Arapo’s fiance wanted to know what happened, and why he wasn’t saved from the fire.

Hart claimed the pair had tried to break back into the house after Hayde had smashed his way out but were unable to battle through the flames to find Arapo.

The Crown case is that the pair’s efforts to go back into the home were a charade for witnesses as they knew he was already dead.

A few days later, Muzammil spoke to Hayde, the jury heard.

The wing of the Minerva Tce home where Arapo lived was engulfed by fire. Photo / Michael Howse

Hayde told him he was outside with Hart when they saw smoke and tried to run back inside, Muzammil said.

He allegedly told Muzammil that Arapo was inside by himself, contradicting Hart’s account.

Neighbour Zelda Dammert told the court today she heard the phrase “I’ve told you yesterday mate” three times followed by the sound of someone being pushed into the home’s french doors and saw the curtains moving as if someone was being shoved into them.

“After that, it just got so intense and I couldn’t handle the abuse and the sounds that I was hearing so I removed myself from the deck,” Dammert said.

“I went into my room because I felt quite sick.”

She heard what sounded like chairs being thrown around inside the home.

“I was so afraid somebody was going to get killed. That was the first thing that came to my mind.”

The trial continues.