Story highlights Pistorius is charged with murder but says he thought he was shooting an intruder

Journalist says Pistorius had prior incidents swept under the rug

One friend says Oscar Pistorius threatened to fight him over a girl

Another friend said Pistorius was a good guy, never aggressive

Oscar Pistorius first gained international fame amid a raging debate over whether his prosthetic legs would give him a competitive advantage in the 2012 Summer Olympics.

Today, the disabled track star finds himself in the middle of a more serious controversy: whether he intentionally shot and killed his girlfriend Reeva Steenkamp , or whether he mistook her for an intruder.

Pistorius has been charged with premeditated murder and his trial is sure to provoke worldwide news coverage (no date has been set yet).

The South African athlete's spectacular fall from grace shocked many who were inspired by his remarkable story of overcoming adversity to become an Olympian and a national hero.

But not everyone.

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"Here, I think, you had a troubled athlete," said South African sports journalist Graeme Joffe. "Not so much this incredible role model for the rest of the world -- no question about that -- but deep down, this was a troubled athlete."

Joffe is one of the few South African journalists who has been critical of Pistorius. He said the PR machine behind the man they call Blade Runner has all but made him untouchable.

"So many incidents have happened and they've been well documented over the last five or six years with Oscar Pistorius," said Joffe, who worked at CNN in the 1990s. "These kinds of cases have disappeared."

The South African media has long adored Pistorius, some would say even protected him, by minimizing his problems. Yet, some of his friends and colleagues have cast doubt on the idyllic image of Pistorius portrayed by the press.

"It's like we were waiting for something like this to happen," said Marc Batchelor, a South African soccer player who socialized with Pistorius in South Africa's glamor and sports circles.

Batchelor described Pistorius as someone who "had a trip switch," quick to get angry and fight. Pistorius caused "a lot of problems," he said.

Batchelor said Pistorius once wanted to fight him because the track star thought his girlfriend was cheating on him. Pistorius, who Batchelor described as drunk, started yelling and swearing over the phone.

"He said he's not scared. If I want to come down there, he knows where I am, and blah blah blah. But I left it," Batchelor told CNN.

One thing many people don't know, Batchelor said, is that Pistorius was armed nearly everywhere he went. He even applied to become a licensed gun collector so he could buy more guns than the four that South Africans are allowed, according to Carvel Webb, chairman of an umbrella organization for South Africa's private gun collectors, including Pistorius.

Just last January -- though the facts are in dispute -- Pistorius' friend and boxer Kevin Lerena said the track star was holding a gun at an outdoor café when it went off. Lerena said Pistorius was showing the gun to a friend.

"That was a major mistake what happened from Oscar's part, it wasn't intentional," Lerena told CNN's Piers Morgan last month . "And that also could have been a very bad event and something that could have been very tragic. We are all very fortunate that day. And after that event, Oscar was very apologetic."

Lerena said the incident was purely an accident.

"That's how dangerous guns can be," he said. "But by no means did I think he was negligent with the gun."

There are no police records of the incident, and CNN could not get a comment from the restaurant. And when questions were asked in the media, an unidentified Pistorius friend said it was he who brought the gun to the restaurant, not Pistorius.

Pistorius crossed paths with authorities in February 2009 when the sprinter said he was nearly killed when the speedboat he was driving hit a submerged object. He was airlifted to a hospital and underwent facial reconstruction surgery. Yet, at the time, doctors downplayed the injuries as minor.

Three days later, local news reported police found alcohol bottles inside the submerged boat.

"We are investigating the possibility that the consumption of alcohol had played a role in the boating accident," said police spokeswoman Maria Mazibuko.

The next day the spokeswoman said she was misquoted, and even said police could not confirm Pistorius was the driver.

And Pistorius' manager strongly condemned the report:

"That's the problem with South African media. They don't get their facts [straight] and they love to speculate," Van Zyl said.

Police eventually dropped their negligent driving charge against Pistorius.

CNN has repeatedly asked the Pistorius family and his lawyers for comment but has been told there would be none. He is next due in court on June 4.

The police have refused to discuss any part of their investigation.

CNN also attempted to reach other friends, colleagues and associates of Pistorius, but all have withheld comment on their relationships with him.

There's little doubt that Pistorius' character and his previous run-in with authorities will be key issues brought up by prosecutors during his trial.

In the meantime, Pistorius has been released on bail and awaits his fate at his uncle's multimillion-dollar mansion in Pretoria, South Africa. He's no longer required to visit police twice a week under the terms of his bail. Instead authorities will now visit him at his uncle's -- and only occasionally.

However his critics viewed him, even the friends who criticized Pistorius' actions defended him.

"He was a good guy," Lerena said, "could have fun with his mates ... but never was he reckless and ever in my company aggressive toward anyone."