Troy Armstrong: Man accused of killing his ex-wife Kristy after running her off the road is found dead in his cell

A man accused of killing his former wife by running her off the road has been found dead in his cell just days before the one-year anniversary of the crash. 

Troy Armstrong, 36, had been charged with murdering his former wife Kristy when he allegedly drove his ute towards her sedan at 140kmh in Molong near Orange, in central-west NSW, on June 9 last year.

Kristy was killed instantly while Armstrong sustained serious brain and spinal injuries which left him unable to walk or take himself to the toilet. 

The couple's two daughters, aged eight and 13, had been in the back of Kristy's sedan and were left with minor injuries. 

On Tuesday, Armstrong was found unresponsive in his cell at the Metropolitan Remand and Reception Centre in Silverwater, western Sydney. 

A Corrective Services NSW spokeswoman said: 'The inmate was immediately given first aid and taken to hospital but was pronounced deceased. 

'As a matter of protocol, Corrective Services NSW and NSW Police investigate all deaths in custody regardless of the circumstances.'

His death comes just days before the one-year anniversary of the fatal crash.  

Armstrong was also facing attempted murder charges related to his two daughters and three counts of breaching apprehended violence orders.

He had not entered any pleas at the time of his death and was due to face a committal hearing on July 11. 

Police allege Armstrong purposely ran his ute into Kristy's sedan while travelling at 140km/h following an argument at their children's primary school.

Kristy had taken out an apprehended violence order against her former husband just two weeks before her death. 

On May 10, Armstrong was ordered to appear in court for the first time with his lawyer asked if he was fit to appear via audio-visual link.

'He is fit to appear,' Armstrong's lawyer Drew Hamilton told Orange Local Court. 

'It does take some work to get him in the AVL suite but he can appear.'

During an unsuccessful bail application last year, Mr Hamilton told the court Armstrong posed little risk to the community as he had part of his skull removed and could no longer walk. 

But police prosecutor Carl Smith said Armstrong was 'an extremely dangerous person' who had left his two daughters living in fear, despite his injuries.

'(They) were terrified before this incident, they're even more terrified now,' Sergeant Smith told the hearing. 

'He knew driving 140km/h into a car of the likelihood that he'd be killing his wife, but (also) anyone else in that motor vehicle.'

Armstrong was held under 24-hour police guard in the intensive care unit at Sydney's Royal North Shore Hospital in the months after the crash.

The couple's two daughters are now being cared for by their grandparents.