Key figures at the centre of an explosive civil court dispute linked to South Australia’s biggest infrastructure project have broken their silence, rejecting allegations of intimidation, threats and underworld involvement.

Jamie Brown, a member of an outlaw motorcycle gang, has been named in bitter court proceedings alleging intimidation and violence were used in an attempt to gain control of labour-hire company Career Boss, which supplied workers to the Torrens to Darlington project.

WATCH ABOVE: Bikie denies threats over Torrens to Darlington project

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The River Torrens to Darlington (T2D) Project is South Australia’s largest road infrastructure project, a $15.4 billion initiative to complete the final 10.5km section of Adelaide’s North-South Corridor.

7NEWS.com.au understands the contract to supply workers is worth millions of dollars.

On Monday, 7NEWS revealed alarming allegations of violent incidents surrounding T2D project, that sparked a political fallout after potential bikie links to the project were alleged. 

Adelaide man Jamie Brown denies any wrongdoing in serious allegations involving an Adelaide road project. Credit: SAPOL/7NEWS

Businessman Rob Cammarano, a shareholder in Career Boss, said his family has spent the past year living in fear after a string of violent attacks across Adelaide that have left his business empire in ruins and sparked a high-level police investigation.

He claims criminal elements were attempting to muscle in on the company and ultimately gain control.

“We’re just very cautious,” Cammarano told 7NEWS.

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“We’re always looking at if anyone’s following us.”

But another, unnamed, shareholder has spoken out strongly rejecting those claims, insisting there had been no interference from Brown.

“I have never been threatened,” she said.

“Not by Jamie, not by any of his associates, friends, by nobody.

“I hold myself pretty high with ethics and morals and I don’t appreciate these false allegations.”

She said she provided a formal statement to police on October 23 disputing the claims.

“A formal statement that these allegations are just that, allegations, and they are not correct,” she told 7NEWS.

Brown has also denied the allegations.

Serious allegations of threats and intimidation surround a multibillion-dollar road project. Credit: 7NEWS

In a statement to 7NEWS, Brown said he categorically rejects any suggestion he had any involvement in Career Boss or the Torrens to Darlington project.

He further denied ever threatening any shareholder of Career Boss, describing the allegations as false and fabricated.

Brown also indicated he intends to fight the claims through the courts.

“I’m waiting for my time in court,” he said on social media.

“I’m going to turn this into a circus.”

The unnamed Career Boss shareholder said she believed Brown and his family had been unfairly affected by the allegations.

“I actually feel for him and his family to have these allegations made which are not true,” she said.

No criminal charges have been laid in relation to the allegations contained in the civil lawsuit.