The 63-year-old, whom the Courier Mail reported is former prison officer Bruce John Preston from Goulburn, has been charged with three counts of murder.

Mount Isa detectives confirmed the man flew to Brisbane of his own accord on Friday and was arrested and charged.

The charges come more than 40 years after the first of three bodies was found in remote Queensland bushland near Mount Isa.

The three had last been seen on the morning of October 5 following their arrival in Mt Isa as part of a motorcycle journey from Alice Springs to Melbourne.

Tim 31, and Gordon, 21 were family friends from New Zealand with a passion for motorcycles.

Karen, 23, was Tim's girlfriend and the trio was on the adventure of a lifetime trekking across the outback.

Once they reached Cairns, the trio planned to head south to Melbourne for Christmas with family.

They never made it.

After their last sighting in the Moondurra Caravan Park, their bodies were found 19 days later in bushland near Spear Creek, 12km north of Mount Isa.

All three died from gunshot wounds.

Preston had been a person of interest, charged with stealing Tim's motorcycle in 1978 for which he was convicted and fined $300.

At the time, he was an unemployed diesel mechanic. Later, in Goulburn, he joined Corrective Services and was awarded a commendation for brave conduct by the Commissioner in 2002.

Detective Senior Sergeant Tara Kentwell said the families of the victims had been told of the charges and were "relieved" by the outcome.

"We believe that there are still witnesses out there who hold vital information and we appeal for those persons to come forward," she said.

Detective Kentwell said the accused was "surprised" by the arrest, but would not comment on a motive other than that he was known to the victims before October 5.

Det Kentwell said it felt "pretty good" to make an arrest four decades after the crime.

"It's a good feeling to provide some closure to these families after such a long time."

The man is expected to face Brisbane Magistrates Court on Saturday charged with three counts of murder.

Australian Associated Press

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