Anthony Stott was last seen at Brisbane airport at 3pm on Sunday after returning from a holiday to Peru

A car belonging to a French language teacher who was hit and killed by a truck after allegedly being held captive on a farm was filmed speeding down a highway without headlights on in the hours before he died.

Anthony Stott, 43, a teacher at prestigious private school St Peters Lutheran College in Brisbane, was run over and killed at 7am last Monday on the M1 near Cudgera Creek in northern NSW, less than 24 hours after he returned from a trip to Peru.

Mark Francis Frost, 46 - known locally as Frosty - and Lauren Claire Grainger, 38, are accused of torturing him for six-and a-half-hours on their nearby farm before he was freed - or managed to escape.

He was allegedly tied to a white chair in their shed with rope around his neck and wrists during the ordeal before somehow making his way to the roadside, where he was hit by oncoming traffic in what has been described as an accident.

Dashcam footage obtained by Nine News showed Mr Stott's silver BMW speeding down the M1 near Cudgera Creek at about 1am on the day he died.

A nearby truck driver flashed his high beam lights toward the driver as the car sped down the road.

About an hour later, the same dashcam recorded the car again. This time it was stopped in the left hand lane.

The car was unlocked and Mr Stott's personal belongings, including keys and wallet, were left inside, police said.

Anthony Stott, 43, was a respected French teacher at Brisbane's St Peters Lutheran College and died about 7am on Monday

It is not clear if Mr Stott was driving the car at the time, but it has since been identified as belonging to him.

At the nearby farmhouse, the teacher appeared brandishing a knife, according to his alleged abductors.

Grainger claimed the couple only detained Mr Stott to find out why he was on their property armed. She claims they let him go, court documents allege.

'I tried to restrain him... I marched him out there [to the shed],' she allegedly told police, according to the Courier Mail.

The couple are charged with detaining Mr Stott with intent to obtain advantage.

They allegedly took photos of him in the chair, restrained with rope around his hands and neck, one of which was shown in Tweed Heads Local Court on Monday as Grainger applied for bail.

Mark Francis Frost, 46, (left) and Lauren Claire Grainger, 38, (right) have been charged with detaining with intent to obtain advantage

Dashcam footage of the moments prior to Mr Stott arriving on their farm show his silver BMW stopped dead in its tracks on the left hand lane of the M1

How a French teacher came to be killed on the side of a highway WHO WAS ANTHONY STOTT? The 43-year-old French teacher taught at St Peters Lutheran College at Springfield HOW DID HE DIE? He was fatally hit by a semi-trailer while walking along the M1 at Cudgera Creek, south of Tweed Heads, on February 10. WHO HAS BEEN CHARGED? Mark Frost, 46, and Lauren Grainger, 38, have been charged with detaining Mr Stott with intent to obtain advantage. They faced Tweed Heads Local Court on Monday. Grainger was denied bail while Frost did not apply for bail. They are accused of holding him captive before he died. COURT HEARS FIRST DETAILS Grainger initially claimed she was asleep and unaware Mr Stott was at the property. Police allege they found a photograph on Grainger's mobile phone of Mr Stott tied to a chair. It's not known if he was released or broke free from the chair. Grainger's charge was adjourned for mention on April 6 while Frost will reappear on Wednesday. Advertisement

Police are yet to find the chair and rope allegedly used to tie up Mr Stott, despite an extensive search of the property.

Grainger allegedly told police Mr Stott was released the next morning and 'casually' walked towards the M1.

Witnesses said he raised his arms as he emerged from bushes by the side of the highway before he was hit.

Police opposed bail for Grainger, allegedly she had not been 'completely honest' with detectives and that knives similar to the one she claimed Mr Stott had were in the farmhouse' kitchen.

Magistrate Geoff Dunlevy denied her bail despite her brother putting up a large bond and offering a place to stay.

He said he was concerned Grainger would interfere with the ongoing police search for the rope and chair - key pieces of evidence.

Frost has not applied for bail and is still behind bars.

Mr Stott was last seen alive landing at Brisbane Airport, he was then allegedly abducted and held at a property in Cudgera Creek in northern NSW. Later, he was struck by a truck and died

Police are yet to find the chair and rope allegedly used to tie up Mr Stott, despite an extensive search of the property (pictured)

The pair are part of a team of vegetable and flower farmers who won Best Lettuce and Best Tomato at the Murwillumbah show last year. Their tomatoes and flowers were regularly sold at a local farmer's markets and stores.

A neighbouring farmer told Daily Mail Australia that Frost seemed like a 'professional' farmer.

Frost and Grainger were both previously witnesses in the trial of a local cattle farmer in 2013, over a pub brawl they allegedly witnessed.

NRL star Craig Field was convicted of Tweed cattle farmer Kelvin Kane's manslaughter at the conclusion of the trial.

Puzzled investigators are examining how and why Mr Stott - a well-respected teacher at St Peters Lutheran College - allegedly ended up at a property in Cudgera Creek.

Mr Stott's silver BMW had been found abandoned on the highway, close to the couple's property, several hours before he was killed

Police are wanting to speak with anyone who may have seen his vehicle last Sunday afternoon - a silver BMW with NSW registration ANL 72Y

Police are probing whether the teacher was known to the accused couple.

Detective Acting Superintendent Brendon Cullen said last week: 'We do not know what that relationship is, we don't know how he ended up in their house or why he ended up there.

'What we do know is he was there and he was detained against his will there... what we don't know is what happened after he left that place.

'We want to speak with anyone on the NSW Far North Coast or across the border in Queensland who may have had dealings with or had spoken with him since Sunday 9 February.

'We're also wanting to speak with anyone who may have seen his vehicle on Sunday afternoon – a silver BMW with NSW registration ANL 72Y.

'Piecing together his movements in the 24-hours prior to his death is crucial and I urge anyone who may have any information to contact Crime Stoppers.'

Investigators aren't ruling out the involvement of illicit drugs in Mr Stott's death and alleged abduction, but noted the teacher was 'by all accounts a fine member of the public'.

Anthony Stott, 43, taught French at St Peters Lutheran College, a prestigious $24,000-a-year school in Brisbane

Supt Cullen also said at this stage there is no evidence pointing to connections to bikie gangs.

In a statement, St Peters Lutheran College Springfield said it was 'devastated' by Mr Stott's 'tragic passing'.

'Mr Stott was a primary school teacher at the College from 2018 and was a popular and well-regarded member of our community,' the school said in a statement.

'This is a very difficult time for the St Peters community and the College is offering support to Mr Stott's family as well as staff, students and families.

'Out of respect for Mr Stott's family, and because this is now an active police investigation, it is not appropriate for the College to make any further public comment.'

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