Detectives allege 59-year-old Darryl “Blinky” Young from Bogie was behind the murder of Mervyn Schwartz and Maree Schwartz and her son Graham Tighe on the remote Shannonvale Station south-west of Bowen on Thursday.
Maree’s other son, Ross Tighe, survived and called police after being critically wounded.
9News has confirmed detectives’ main line of inquiry is whether a boundary fence dispute triggered the alleged incident.
Young’s property remained a crime scene on Saturday.
It is understood to include a number of gold mine shafts from the 1800s.
Locals said they were in disbelief about the three deaths.
“People just shake their heads in disbelief,” Whitsunday regional councillor Mike Brunker said.
The family of Graham Tighe, including his partner and two children, made a mercy trip to Mackay Base Hospital on Saturday.
They are there to support Ross, who remains in hospital in a serious but stable condition.
He has told police his version of events.