Slain bikie chief shot dead by a SNIPER at a drag race in front of terrified children had survived several previous attempts on his life - as his daughter denies he'd fallen out with the Rebels gang

A Rebels bikie boss survived a series of close calls before he was executed in front of horrified families and young children in what police have described as a precision sniper attack.

Nick Martin, 51, was fatally shot in the back while attending the Outlaw Nitro Challenge drag racing event at the Perth Motorplex track with his wife, step-daughter and her partner on Saturday night.

A five-year-boy sitting nearby also suffered non-life threatening wounds as did former Gold Coast Bandido bikie Ricky Chapman, the partner of Martin's step-daughter Stacey Schoppe. 

As the hunt for the gunman continues, Martin's grieving family has hit back at claims by WA Police Commissioner Chris Dawson he had recently 'lost his status' in the Rebels bikie gang. 

Nick Martin (pictured with his wife Amanda) was killed in a terrifying public shooting on Saturday night

His daughter Tia Martin, 22, insists he wasn't stood down by the club but confirmed he was legally barred from communicating with Rebels members and 'would have gone to jail' if he was caught associating with them due to an ongoing court case.

'He was on charges and was on non-association and was not able to talk to anyone in the club in months,' Ms Martin told The West Australian.

'(His assassination) definitely did not come from within the club.

'We are family.'

Reports, denied by his daughter, suggested his shooting was in retaliation for alleged problems he had in the club.

Daily Mail Australia is not suggesting any associate of Mr Martin's was responsible for his death. 

Prior to his death, Martin was a well-known identity in the Perth underworld and had survived a series of attacks.

Step-daughter Stacey Schoppe was at the track with her partner Ricky Chapman (pictured together). Ricky was also injured

He was shot in the arm while arriving at his Balcatta home, in Perth's northern suburbs, in March 2011. 

At the time the Rebels were locked in a feud with the Rock Machine Gang and its member Benjamin Spikes was convicted over the shooting.

One year later Martin's Balcatta home was the target of another attack and his car was firebombed.

Martin's heartbroken wife Amanda paid tribute on Sunday by replacing her Facebook profile photo with one of her late husband, which was inundated with comments from shocked friends.

His devastated step-daughter also posted a heartfelt tribute.

'I tried, we tried so hard to keep you alive dad,' Ms Schoppe posted to social media.

'This is one of the most heartbreaking traumatic experiences I've ever witnessed. To my mother, be strong we will get through this. I'm sending love to his immediate family and friends.' 

Paramedics tried to save Nick Martin's life as shocked families watched on in horror after the shooting on Saturday night (pictured, paramedics at the scene)

Martin's step-daughter Stacey Schoppe was among those who tried to revive him

Other family members described Martin as a loving father, grandfather and husband.

'He would do anything for anyone and people don't know half of who is actually is,' one told Seven News.

Commissioner Dawson claimed there had been recent friction within the Rebels club and revealed Martin survived multiple attacks before his was abruptly cut short.

'Nick Martin had lost his status within the Rebels outlaw motorcycle gang. He was a long-term president, he had been shot a number of years before (in 2011) and survived that shooting,' Commissioner Dawson told reporters on Sunday.

'He was facing criminal charges over some financial crime matters. He had lost his status within the Rebels club in Western Australia.'

Police believe a sniper fired a single precision long-range shot before fleeing the venue.

They're also prepared for bikie gang revenge attacks and have put outlaw bikies on notice.

Nick Martin's shattered wife Amanda uploaded this photo of her late husband on Facebook and paid tribute to his life

Amanda Martin's Facebook page is flooded with photos of husband Nick (pictured together)

'We're at a heightened state of readiness to ensure there are no retaliatory attacks but that's the nature of these gangs we're dealing with,' Commissioner Dawson said.

'We will be relentless in our policing of outlaw motorcycle gangs, we have been for many years and will continue to do so. Police are carrying out an extensive investigation.

'We will make every effort to bring those responsible to justice.'

A five-year-old boy, who was sitting nearby, was also injured and treated for a 'minor wound' by paramedics. 

Sam Hijazi said his son Eli was doing 'OK'.

'Yeah he's fine. He was a bit shaken up last night but he's doing OK now,' Mr Hijazi told The West Australian.

'He didn't even need hospital. It really wasn't bad (the injury).'

Commissioner Dawson was furious innocent children were caught up in the innocent.

Nick Martin (pictured with wife Amanda) was remembered as a loving father, grandfather and husband

Fears are mounting of an all-out bikie war after a Rebels boss was gunned down at a family drag racing event, just weeks after he was involved in a brawl (pictured, Perth Motorplex at Kwinana Beach)

'It is an example of where innocent parties can get caught up in this violent criminal gang which has resulted in a homicide,' he said.  

'We all must be outraged at this violent criminal behaviour, a five-year-old boy who's received fortunately superficial wounds, but these criminals don't stop and have regard to human life.

'The fact that this shooting occurred in a public open place with many people around, including children shows the nature of these violent criminal gangs.

'There are many people, totally innocent, who have now been subjected to the most horrific of crimes involving gangs.' 

The event was called off following the incident. 

Terrified parents said they tried to protect their children and take them somewhere safe following the commotion.

'We just heard a massive bang and we thought it was from a car,' spectator Michaela Marshall told Seven News.

'It's horrible, it's heartless. My 10-year-old child was there.' 

Commissioner Dawson said the community had become 'outraged at this type of violent criminal behaviour'.

'This is not the Western Australia that we want to live in.'  

The shooting comes after Martin was allegedly involved in a brawl with a Hells Angels bikie at The Sandbar, in Scarborough, on November 24.

The shooting comes after Martin was allegedly involved in a brawl with a Hells Angels bikie at The Sandbar, in Scarborough , on November 24 

Daily Mail Australia is not suggesting the two incidents are linked. 

Security cameras filmed two men speaking with each other and shaking hands before coming to blows among staff and patrons at the trendy beachside bar.  

Pub goers could be seen in the footage running away from the scuffle as furniture was tossed around the bar during the violent fight. 

A man wearing a white shirt landed several huge punches and knees in the brawl while horrified onlookers watched on.

Martin was taken to Royal Perth Hospital while the other man was charged by the National Anti-Gangs Squad for 'fighting in public causing fear'. 

In April this year, Martin and his wife were charged as police investigated alleged extortion and money laundering schemes and were due to face court next week. 

Fellow Rebels members recently accused Mr Martin of misappropriating funds and blamed him for a mass defection of members to the rival Mongols gang, Nine News reported.

Nick Martin, 51, was watching a race at the Perth Motorplex, at Kwinana Beach, at 8.30pm on Saturday when he was shot