Police are searching for a motive after the suspected murder of a Queensland man who went through an industrial wood chipper last year.
Reports at the time indicated Bruce Saunders, 54, died after going through the wood chipper while clearing a driveway at Goomboorian near Gympie on November 12 about 7.40pm.
Detective Inspector Gary Pettiford said the horrific scene had affected emergency workers.
"A man going through a wood chipping machine which is designed to shred plant material, you can imagine the scene," he told reporters on Friday.
"All the emergency services personnel that went there were extremely good at what they did and they wouldn't be human if they weren't affected by it."
Det Insp Pettiford said Mr Saunders' death was treated as an accident until a person came forward to police with information.
"Since that night information has come to hand to indicate the reporting of the death, which was reported as accidental, may not be the case," he said.
Police have since searched the area again finding new evidence and have also identified a number of persons of interest.
It's understood Mr Saunders was cleaning the driveway with two friends, as they had done for the previous two weekends, to help a female friend trying to sell her home.
"They were there in an act of goodwill," Det Insp Pettiford said.
The woman had been "extremely upset" by the incident, with Mr Saunders' family also "shocked" by what had occurred.
Police are confident they will find the suspected killer where charges will be laid.
"We will not give up on this investigation," Det Insp Pettiford said.