British athlete Martyn Rooney has sent his sympathy to all involved in the tragedy surrounding Oscar Pistorius' alleged murder of his girlfriend, Reeva Steenkamp.
Rooney, who trains with Pistorius and was with him only last week, has been too upset to comment directly on the news.
In a statement released through British Athletics, the 400m runner said: "My thoughts and prayers go out to the families and friends of those involved.
"I will not be making any further comment on the events of this week and ask that this decision is respected."
And Jamaican sprinter Shelly-Ann Fraser-Pryce, who retained her 100m title at the London Olympics, said she first heard the news when she arrived in Britain to take part in this weekend's Birmingham Grand Prix.
Fraser-Pryce said: "When I came off the plane at Heathrow and I gave the immigration officer my passport she said, 'What's your purpose for being here?'
"I said, 'I'm an athlete.'
"She said, 'do you know Oscar Pistorius?' I said, 'Yes'. She said, 'He shot his girlfriend.' I was like, 'are you serious?'
"I've not really drawn a conclusion yet. I've not really processed the information. I've not heard what he has to say so it's very difficult to actually comment."
Miss Steenkamp was found dead at Pistorius' home on Thursday, having been shot several times.
Pistorius was arrested shortly after and appeared in court today, charged with premeditated murder. He denied killing Miss Steenkamp, and his agent released a statement saying: “The alleged murder is disputed in the strongest terms.”
“Oscar Pistorius has made history as an Olympic and Paralympic sportsman and has been an inspiration to others the world over. Our thoughts and prayers today should be for Reeva and her family - regardless of the circumstances of this terrible, terrible tragedy.”
He will remain in custody until a bail hearing on Tuesday.
Today, American sprinter Carmelita Jeter added: "I've seen him a couple of times at track meets, and he has always spoken to me and been very nice, so that's all that I know of him.
"I don't really know him as a person. It's definitely a sad situation, but the only thing I know is the same thing I saw on the news.
"I don't like to speculate. It will soon come out exactly what happened."