Two Bundaberg residents, a 71-year old man and a 64-year old woman, were each charged with one count of unlawful possession of a firearm, broadcaster ABC reported
The woman, a licensed trainer, was also charged with obstructing police.
Michael Beatty, spokesman for RSPCA Queensland, told ABC that inquiries were continuing. The animal rights organization is assisting Queensland police in their investigation.
"A lot of people in the area who were involved in the greyhound industry were questioned, and it was as a result of information given to us that the joint Queensland Police Service and RSPCA investigation team made those arrests," he said.
At a press conference Thursday
, Queensland Police Minister Jo-Ann Miller described the discovery of the carcasses, which followed a tip-off from a member of the public, as sickening.
"What I believe has happened here has been the mass murder of 55 greyhounds outside of Bundaberg," she said.
She promised a zero tolerance approach to animal abuse.
"The people who have perpetrated this crime, to me, are oxygen thieves, they are cowards and they are pathetic."
Detective Superintendent Mark Ainsworth said the crime scene was "nothing short of abhorrent."
"Some of the greyhounds were in different states of decay and that would sort of indicate to us that they've been dumped there over varying periods of time," he said.
"The postmortem will reveal the cause of death of these dogs. However I will comment that a number of spent .22 cartridge shells were found in the vicinity."
He said there had been a number of bushfires in the area surrounding the dumping site, which would also be factored into the investigation.
Beatty said it appeared the dogs would have been culled by people involved in greyhound racing.
"There's always been a lot of wastage in the greyhound industry," he said in a statement.
"The indications are that these may just be young dogs that didn't have the speed, basically. But that's really all we know."
Industry under fire
Australia's greyhound racing industry has been under intense scrutiny since a television investigation revealing the illegal use of live bait
in training dogs aired in February.
The investigation, on the ABC network, showed footage of trainers fixing live possums, piglets and rabbits to lures to be chased and mauled to death by dogs, prompting a wave of bans and suspensions from the sport.
Australians wager AU$4 billion ($3.03 billion) a year on greyhound racing, according to the ABC report.
Ainsworth said the Queensland police had established a joint taskforce with the RSPCA to investigate the industry in the wake of the report.
"We've not even tipped the iceberg as yet," he said, appealing for those involved in the industry to come forward.
"You know who you are, you know what you've been involved in, and now is the time to stand up and be counted," he said.
"It will only be a matter of time before we get around to knocking on everyone's door."
Racing Queensland did not respond to a request for comment.