Australia's harness racing industry, known as the trots, was Friday rocked by fixing allegations as police charged a trainer and flagged further arrests in what they described as a systemic practice.
Queensland state police said the 46-year-old man, who was not named, was charged with one count of match-fixing after a 10-month "protracted investigation... into systemic match-fixing in the harness racing industry".
"There is a ... loose cartel of drivers and trainers who are involved in systemic race-fixing activity," Queensland Racing Integrity Commissioner Ross Barnett told reporters in Brisbane.
"How that occurs depends from race to race. They all get together and decide on driving tactics or who will win the race, how they will win it. Those things change from race to race, from meeting to meeting.
"What we are talking about is serious, organised, criminal activity."
Trotting, involving drivers racing around a track on carts -- known as gigs or a sulky -- behind horses, first emerged as a sport in Australia in the 1800s.
It also has a following in countries including France and the United States.
Barnett said the investigation was sparked after people within the industry expressed fears that fixing was taking place.
It is the first time such a charge has been used since it was recently added to Queensland's criminal code, Barnett said, and attracts a maximum sentence of 10 years' jail.
The man is due in court next month.