The City Press newspaper said that the South African Revenue Service fined the double-amputee runner "less than one million rand" (under $105,000), which he paid.
Pistorius' uncle, Arnold Pistorius, said "Oscar is tax compliant" in a brief statement to The Associated Press later Sunday without elaborating further on any of the details of the report.
Oscar Pistorius is charged with premeditated murder for the Valentine's Day shooting death of girlfriend Reeva Steenkamp at his upscale house in Pretoria in the pre-dawn hours of Feb. 14, and will appear in court on June 4 for what prosecutors say will be a brief hearing while the police investigation of his killing of Steenkamp continues.
He denies murder and says he shot Steenkamp in error after mistaking her for an intruder in his home.
The 26-year-old Pistorius declared in a court affidavit during his application to be freed on bail in February that he earned around $630,000 a year and owned three houses and a vacant plot in South Africa with a combined value of nearly $1 million.
The City Press said he owns another house in Johannesburg, which the newspaper claims he bought for 9.8 million rand ($1.02 million) this year. That house was not declared as part of his assets in his affidavit.
Much of Pistorius' income is believed to have come from big-name sponsors Nike and eyewear company Oakley, which suspended their deals with the Paralympic champion after he was charged with murder.
His family has denied previous media reports that he is facing financial ruin because of spiraling legal costs, saying in a statement in March that those legal bills, while huge, were "under control."
"While the family doesn't deny that Oscar's legal expenses are massive and that he has sold off some of his investments, including his racehorses ... Oscar will evaluate the cost situation on a day-to-day basis and make decisions as required," the family said.
Pistorius, now free on $113,000 bail, also has decided to step away from competition for the rest of the year to focus on his upcoming trial, which is likely to be long and expensive for him and where he will face a life sentence in prison with a minimum of 25 years before parole if convicted of premeditated murder in Steenkamp's killing.
One of Pistorius' teammates from last year's London Olympics, LJ van Zyl, said in Britain that the Blade Runner's case and his absence from track competition also was taking a heavy toll on South African athletics and its other athletes.
"If Oscar is at the competition, the South African stadium is full and now that has gone," said Van Zyl, who ran with Pistorius on South Africa's 4x400 relay team in the Olympic final in London and trained at the same track as the double-amputee in Pretoria. "So athletics is really taking a dip now he is off the track. In the beginning it was really tough for every one of us."
"It was media crazy at the track. Now it's still painful for all the athletes. It's sad, but I try to focus on my thing," he said.
Van Zyl said he was planning to travel and stay with Pistorius in Manchester for Saturday's Great City Games before Pistorius had to cancel all his competitions in the wake of Steenkamp's death and his murder charge.
"I get like a weird, sorry feeling and I also miss Oscar," Van Zyl said. "We planned to stay together here and also travel to Manchester and now it's all gone."
Prosecutors say Pistorius' June 4 court hearing, the first since bail proceedings and his first public appearance in nearly four months, will likely take less than 10 minutes and the case will be postponed until a date in August while police continue to gather and analyze evidence and identify and interview witnesses.
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