Police have charged a 59-year-old man with three counts of murder and one of attempted murder following Thursday's shooting in remote north Queensland.
Police have alleged the suspect had invited members of another family to a meeting to settle a dispute before their deaths.
Police said Mervyn Harold Schwarz, Maree Anne Schwarz and Graham John Tighe were shot dead at the front gate of a cattle property outside Bogie, near Collinsville on Thursday morning. Another family member, Ross Tighe, managed to flee the scene despite being shot in the abdomen, they said.
Ross Tighe had fled in a red ute and alerted police to the shooting of his family before being flown to Mackay base hospital earlier in a critical condition and undergoing surgery.
Related: North Queensland shooting: police confirm three dead near Collinsville and man in critical condition
Police alleged there had been "a conversation" between the family and the man who has been charged the night before the shootings.
On Friday Acting Supt Tom Armitt said the suspected shooter, his son and a female member of the family were present at Thursday's meeting. He said the trio were arrested overnight, along with two members of a power company who had been working on the property but were not believed to be involved in the dispute.
All gave statements and were released without charge, except the 59-year-old man. He is due to appear in Proserpine magistrates court on Monday.
Armitt said the suspected shooter was arrested on his property.
He said police received confused reports about where the crime scene was and spoke to the vast sizes of the properties, "tens of thousands of acres" large and a 45-minute drive between the neighbouring homes.
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Further complicating the investigation was that police initially had "no idea who or where the [alleged] shooting offender was" but believed he was armed with a rifle, meaning officers were "in danger of being shot from any distance".
"So that was slow and meticulous work and extremely brave of the officers who were involved," he said.
A special emergency response team were called in to perform "armed clearances of the properties".
Police said the arrested man was a long-term resident of the area, known to police, while the victims were relatively new to the area.
He said there were a lot of people mustering cattle in the area at the time and called on anyone with information to come forward.