A farmer in Australia has gone on trial accused of kidnapping and raping a Belgian backpacker in a shed during a two-day ordeal.

Gene Charles Bristow, 54, has pleaded not guilty to attacking the 24-year-old woman in rural South Australia in 2017.

Prosecutors say she was chained up in a pig shed and repeatedly raped after going to the farm believing she had been given work. She was later freed.

Mr Bristow's lawyers have called the allegations "an invention".

On the first day of the trial, the District Court of South Australia was told that Mr Bristow had contacted the woman after she wrote on classifieds website Gumtree that she was seeking work.

He then arranged to drive her to his farm in Meningie, 150km (90 miles) south-east of Adelaide, the jury was told.

Prosecutor Michael Foundas alleged that Mr Bristow threatened the woman with a fake gun after they arrived at the farm, before trapping her in an "old, dirty pig shed".

'Thought-out plan'
The jury was told that the woman was repeatedly sexually assaulted in the shed, which was located out of sight from a house that Mr Bristow shared with his family.

"This was a premeditated and thought-out plan," Mr Foundas told the court in Adelaide.

"A plan to lure a young female backpacker to his farm where the unlucky victim would be held against her will and sexually abused by him," he said.

The court heard that the woman managed to break free at one point and use her laptop to send messages to relatives and police, who began a search.

However she then re-shackled herself because Mr Bristow had threatened to kill her if she tried to escape, Mr Foundas said.

Prosecutors said Mr Bristow released the woman the next day, driving her to a town, because he was spooked by police search efforts. She was later found by authorities.

The defence team said it did not contest that the woman stayed overnight at the property, but rejected that the woman was held against her will. Mr Bristow also denies that any sexual assaults occurred.

The trial continues.