Police found Lasslett and Littlewood's bodies inside a converted shed on Lasslett's rural property when officers arrived about 8.05pm on February 11 last year, the jury heard.
After the alleged murders Samuel texted his partner Sarah Lee Tarei asking her to pick him and Anthony up at Waitakaruru near Ngātea, which she did, the Crown says.
The trio then headed back to Auckland, the jury heard.
Tarei, 25, is also on trial defending a charge of being an accessory after the fact to the alleged murders by assisting him to evade arrest.
Samuel Fane was arrested in Christchurch on February 14, 2020.
His defence lawyer, Simon Lance, argues Anthony Fane, 33, was solely responsible for the shootings and a further death discovered days later.
During questioning by Pollett yesterday, Jesse Charles Fane, who lives in Papakura, said his deceased brother told him he planned to confront Lasslett.
Jesse Fane initially gave evidence that Anthony told him he was going to Omanawa to find Lasslett to "sort him out" and "possibly kill him".
Anthony and his partner Jessie Lee Booth and their oldest child lived at Lasslett's property several years earlier, before moving to Lynwood Place in Brookfield, he said.
Jesse said the day before the shootings he drove to Samuel and Tarei's house in Papakura and Anthony was also there and described his brothers' demeanours as "normal".
While having a coffee and smoke they had a "catch-up", he said.
"Such as Ants being in Auckland and him having problems about his depression, his mental health and stuff. He was telling us he wasn't feeling right."
On February 11, the day of the alleged murders, Jesse said he did not go to work, and Samuel turned up at the house driving a blue Ford Territory.
The Crown says Lasslett's security camera captured the vehicle driven by Anthony Fane and Samuel in the passenger seat arrive at Lasslett's home at 7.29pm and leaving at 7.39pm.
Jesse initially told the jury he did not know at the time why Anthony wanted to confront Lasslett and possibly kill him nor why Samuel insisted he must go with him.
But Pollett challenged Jesse's in-court evidence and reminded him several times about the sworn statement he gave to Tauranga Detective Tim Bonner on February 14, 2020.
Jesse agreed he signed the statement as being "true and correct" and told Detective Bonner that his brothers left Papakura in the Ford Territory around noon on February 11.
He also said Anthony had a light grey or grey backpack and learned that in the bag was a sawn-off .22 calibre gun and thought his brother had "cut it down".
When pressed Jesse agreed he told Bonner that Anthony told him "they" were going to Tauranga to get Lasslett and kill him, meaning "he and Samuel" were going to Omanawa.
Anthony wanted to go alone but Samuel insisted he must go with him, he said.
Jesse said he found out about the Ōmanawa shootings firstly from media reports then from Anthony himself after he woke him up either later that night or early on February 12.
Samuel was at the house as well, he said.
"Ants said that he got him, he finally f****en got Lass. He was proud of what he did."
Jesse said Samuel left in a Silver Toyota to go on a road trip down south "he believed" and Anthony left in his own car.
He said Anthony later messaged him that he wanted to see his children and he and their mother Donna Fane met up with him at a park area near Miranda.
"He told me that he was happy that he had finally got Paul," Jesse said.
Anthony was "paranoid" and his mind was "all over the place" and their mother was apprehensive about having him back at the house.
On February 13 Anthony again wanted to spend more time with his children and they visited a trampoline park in Takanini, he said.
"Anthony told me that he loved his kids and he was happy that he had got Lass but it was unlucky for the other guy, it was a case of wrong place, wrong time."
Jesse said his brother told him he killed them both but he was not going to go back to jail and "it was going to be a gunfight to the end".
Anthony still carrying the grey backpack gave his children "cuddles and final goodbyes" and drove off in his car and that was the last time he saw him.
Jesse said he later saw a news report about the shooting of a person in Tauranga on February 13 and recognised Anthony's car and drove to Tauranga to find him.
On his arrival at Tauranga police station, he was told Anthony had been fatally shot by the police and during his lengthy police interview also learned that Booth was dead.
Booth's body was found at a Lynwood Pl, Brookfield, address on February 14 when police went to do a welfare check after her family could not contact her.
The cause of death was from multiple crossbow bolt wounds to her head, the Crown said.
The jury earlier heard that police believed Anthony Fane killed Booth on about February 9, 2020, with the crossbow and bolts he bought about a month earlier.
Earlier this week Donna Fane told the jury that her older son Anthony Fane told her he carried out the Ōmanawa shootings and he wanted to go out in a "blaze of glory".
Anthony also told her he was "happy" he had carried out the alleged murders as he believed Lasslett and his partner had been having an affair.
Donna said Anthony also told her "he couldn't believe how easy it was".
"I was in shock and disbelief. I was quite fearful for all of us and I did not want Anthony to come back to my home."
She said Anthony refused to go to the police and knowing he needed to be stopped she called the police Crimestoppers line.
The trial continues today.
