Brian Burston and James Ashby at Parliament House: One Nation adviser and ...

A Senator who sensationally quit One Nation has violently clashed with Pauline Hanson's top adviser at Parliament House amid bombshell claims and counterclaims of sexual harassment. 

The heated confrontation between United Australia Party Senator Brian Burston and One Nation adviser James Ashby unfolded after a function in Canberra on Wednesday. 

Pictures showed the pair grappling with each other after Senator Burston, who left One Nation last year, accused Senator Hanson of sexually harassing him in the past.

Mr Ashby was seen raising a fist at Senator Burston, who later shared images of his bloodstained hand. 

The heated confrontation between United Australia Party Senator Brian Burston (right) and One Nation adviser James Ashby (left) unfolded in Canberra on Wednesday

The heated confrontation between United Australia Party Senator Brian Burston (right) and One Nation adviser James Ashby (left) unfolded in Canberra on Wednesday

Senator Burston shared images of his bloodstained hand (pictured) following the confrontation

Senator Burston shared images of his bloodstained hand (pictured) following the confrontation

Pictures showed the pair grappling with each other after Senator Burston (left), who left One Nation last year, accused Senator Hanson of sexually harassing him in the past

Pictures showed the pair grappling with each other after Senator Burston (left), who left One Nation last year, accused Senator Hanson of sexually harassing him in the past

Mr Ashby later provided a photo which he claimed showed the door to Senator Hanson's office smeared in blood, but Senator Burston denied having anything to do with the marks on the door. 

Senator Burston claimed the drama began when Mr Ashby approached him as he and his wife were leaving the function.  

He claims he was injured when he tried to grab a phone Mr Ashby was waving in his face.

'I told him to f*** off. I lost it. I grabbed him and I pushed him up against the wall. I defended myself and my wife, physically,' Senator Burston told The Daily Telegraph. 

Senator Burston claims he was injured when he tried to grab a phone Mr Ashby was waving in his face.

Senator Burston claims he was injured when he tried to grab a phone Mr Ashby was waving in his face.

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