Oscar Pistorius & Reeva Steenkamp

Donald Trump thinks Oscar Pistorius is getting off easy for killing his girlfriend -- saying the Olympian's 5-year prison sentence is absolutely "ridiculous."

Trump just posted a video about the sentencing on Instagram -- expressing his anger at the legal system in South Africa ... which will reportedly allow Pistorius to get out of prison after only serving 10 months.

Oscar spent Tuesday night in a single cell in the hospital wing of the South African prison -- because officials believe he suffers from extreme depression.

Former Olympic hero Oscar Pistorius was sentenced to 5 years in prison for killing his girlfriend on Valentine's Day 2013.

Under South African law, Pistorius will have to serve at least 10 months before he can ask for parole.

In addition, Pistorius was given a 3-year suspended sentence on a firearms charge (unrelated to Steenkamp), but it was suspended for 5 years, so long as he's not found guilty of another crime where there's negligence involving a firearm during that period.

Pistorius had previously been found guilty of culpable homicide in the death of Reeva Steenkamp. He maintained throughout the trial he thought she was an intruder.

Oscar Pistorius should be BANNED from running track FOR LIFE ... so says U.S. Olympic legend Sanya Richards-Ross ... who says it pains her to say it because she used to be tight with Blade Runner.

Sanya -- who won FOUR gold medals from '04 to '12 -- was out in NYC when we asked her about the International Paralympic Committee's pending decision on whether Oscar should be able to compete in the next Paralympics.

Of course the controversy stems from the fact that Oscar was convicted of manslaughter in the death of his GF Reeva Steenkamp ... and the IPC has said it would make a decision about Oscar's future based on his upcoming sentencing.

But Sanya has already made up her mind -- "At the end of the day, there was a woman that ended up dead. I don't think he should have the privilege of competing in the sport anymore."

Former Olympic track star Oscar Pistorius was found guilty of culpable homicide Friday morning by a judge in South Africa, and was also found guilty of one other weapons charge.

Sentencing for Pistorius is still weeks away. There is no minimum sentence for culpable homicide under South African law and the typical maximum sentence is 15 years, with the average sentence being about 5-8 years.

Pistorius was found not guilty on two of the three weapons charges he was facing. He was only found guilty of the charge involving a shooting at a restaurant. That charge has a maximum sentence of five years.

Pistorius admitted to shooting and killing his girlfriend, Reeva Steenkamp, on Valentine's Day of 2013 … but maintained he thought she was an intruder.

The judge in the Oscar Pistorius murder trial ruled he cannot be found guilty of premeditated murder in the killing of his girlfriend, Reeva Steenkamp, but he can face other possible verdicts, including culpable homicide.

Judge Thokozile Masipa cast doubt on witness testimony and said she believes the media coverage of the high-profile trial contaminated testimonies.

If found guilty of culpable homicide, there is no minimum sentence under South African law ... it's completely up to the judge.

The Lego-artist who's been posting Lego recreations of the Oscar Pistorius murder trial tells TMZ Sports he's been getting DEATH THREATS from people upset with his work.

We spoke to Armando Tejada ... who says he initially decided to document the Pistorius case because, "I've been fascinated by the trial" ... plus, he had a Legos set from the 2012 Olympics, which came with a tiny Pistorius figure.

The images are NOT graphic -- they mostly chronicle Pistorius interacting with the judge and his lawyer in the South Africa courthouse where his trial is being held.

"I don't plan on posting any graphic depictions of the murder or any scene that shows the victim Reeva Steenkamp out of respect," Tejada tells us.

Still, Tejada -- who lives in Chicago -- says some people are so mad they've threatened his life.

"I've received death threats," Tejada says ... "I understand why people would be upset about it. There's a very thin line and I'm sure I've crossed it."

We're told one of threats involved shooting Tejada with a gun.

Police photos of Oscar Pistorius, taken shortly after he shot his girlfriend last year, were shown in court on Friday ... showing the former Olympic hero standing on his blood-stained prosthetic legs and wearing shorts covered in blood.

Earlier this week, Pistorius vomited in court after a pathologist gave gruesome details about the injuries suffered by Pistorius' girlfriend, Reeva Steenkamp, when he shot her last Valentine's Day.

Pistorius claims he shot Steenkamp by mistake, thinking she was an intruder. If convicted, he faces 25 years to life.

Olympic sprinter Oscar Pistorius arrived to court in South Africa for Day 1 of his murder trial Monday -- and it's already getting intense ... with a neighbor saying she heard "bloodcurdling screams" the night of the shooting.

Pistorius -- aka "Blade Runner" -- shot his girlfriend Reeva Steenkamp on Valentine's Day 2013 -- and he's been charged with premeditated murder. Oscar pleaded not guilty to the shooting -- and claims it was accidental because he thought Reeva was an intruder who got inside the house.

Today, Oscar's neighbor recounted what she remembered from that night -- "Just after 3, I woke up from a woman's terrible screams. Then I also heard a man screaming for help. Three times he yelled for help."

The neighbor said her husband immediately called authorities.

Photos of the blood-spattered bathroom where Oscar Pistorius shot his girlfriend to death have surfaced on the web ... and they could prove to be crucial pieces of evidence in the runner's defense.

The pics were taken from outside the bathroom door in the Blade Runner's South African mansion ... and show two bullet holes in the bathroom door ... along with a pool of blood by the toilet ... and a blood trail leading to the stairs.

Another pic shows blood drops on the stairs ... where Oscar says he carried Reeva while trying to call for help.

Oscar admits he shot and killed Reeva Steenkamp on February 14 ... but insists it was an accident.

In fact, Pistorius told investigators he grabbed his gun and fired 4 shots into the bathroom that night ... but only because he thought an intruder snuck into his house and was hiding in the toilet. The holes in the door could back Oscar's defense ... that he truly didn't know who was in the bathroom when he opened fire.

Of course, the person in the bathroom was Reeva -- who ultimately died from her wounds. Oscar was arrested and charged with murder.

Oscar Pistorius says the constant snarking about his murder charge is killing him.

The former Olympian's family issued a statement whining about South African tabloids and social media boo-birds, saying they are deeply disturbed by the "disregard that is being shown by some ... for the profound pain that Reeva’s family and friends are going through."

"For Oscar the process is 'incredibly overwhelming' as he struggles not only to deal with manner in which he lost his girlfriend, but also his role in it." (Read: The part where he shot her multiple times back in February -- he claims he thought she was an intruder).

The statement goes on and on ...

"There is not a moment in the day that Oscar does not mourn for his girlfriend and Reeva’s family, and all those who were close to her, are in his thoughts constantly."

Not that it's slowing him down ... Pistorius is free on bail and was seen jogging on a track in South Africa last month.

Oscar Pistorius returned to doing what he loves recently -- running on a track on a beautiful day with the sun beating down on his face ... while the girlfriend he shot to death is still dead.

Despite the fact he admitted to shooting Reeva Steenkamp back in February, the judge granted the former Olympian bail ... allowing him to roam around South Africa like a regular non-killer person.

Oscar was pictured jogging on a track at a university in S.A. on March 24.

Pistorius -- who's been charged with murder -- says he doesn't intend to compete in any races ... but reps for the runner say family and friends have encouraged him to continue training because they believe it will help him cope with the trauma.

Oscar Pistorius insists he WILL NOT enter any track meets in the near future ... even though a judge has cleared the way for the accused murderer to compete again ... TMZ has learned.

Pistorius -- who was known as "Blade Runner" before he was known as "That Guy Who Probably Murdered His Girlfriend" -- scored a huge court victory today when the judge eased his bail restrictions so he could leave the country to compete in races.

As part of the deal, the 26-year-old sprinter must run his travel plans by officials at least one week before he leaves the country.

But Oscar's rep tells TMZ ... "Oscar does not intend to compete. He merely challenged the travel restrictions imposed, since he was not considered a flight risk during the bail hearing."

The rep continues, "At this point in time there are no plans for him to travel at all."

Girlfriend killer Oscar Pistorius is NOT on the verge of taking his own life -- despite multiple reports to the contrary -- this according to a source very close to Oscar.

Various reports hit the Internet this weekend claiming Oscar was suicidal ... after a man named Mike Azzi -- claiming to be one of Oscar's "dearest friends" -- told a British media outlet he feared for the Olympian's mental state, saying "I would say that, just by speaking to him, he is a broken man. I’d go as far as to say he would be on the verge of suicide."

But the source -- who has daily contact with Oscar -- says it's just not true. "Oscar is absolutely not suicidal and any reports out there are just false. Oscar is grieving like anyone would be ... but he is not suicidal."

The source also says Mike and Oscar were business acquaintances, not friends -- Mike trained Oscar's horses ... that's it, and he's in no position to know Oscar's mental state.

Oscar Pistorius is planning a private memorial service to honor his girlfriend, whom he shot and killed on Valentine's Day.

The memorial for 29-year-old Reeva Steenkamp is scheduled to take place tonight at the home of Oscar's uncle, where the Olympic sprinter has been staying since he was released on bail last week.

Oscar's rep released a statement, saying, "Oscar specifically requested the memorial service as he continues to grieve and remains in deep mourning for the loss of his partner Reeva."

The rep adds, "Since it is such a sensitive issue, Oscar has asked for a private service with people who share his loss, including his family members who knew and loved Reeva as one of their own."

Oscar -- who stands accused of murdering Steenkamp -- claims he shot her by accident, thinking she was an intruder.

Oscar Pistorius' older brother faces up to 15 YEARS in the slammer for allegedly killing a female biker during a fatal car crash -- this according to new reports.

Carl Pistorius has been charged with culpable homicide -- according to eNCA news, a South African TV channel -- stemming from a car crash in 2010, in which prosecutors say his reckless driving led to the death a motorcyclist.

Carl's lawyer recently told the station that Carl "deeply regrets the accident," but was adamant his client was not drunk at the the time of the collision, adding, "There is no doubt that [he] is innocent and the charge will be challenged in court."