"There have been rumors about him not being a nice person, and not having a good track record as far as some girlfriends are concerned," he said. "I've never encountered that side of Oscar Pistorius, because every time I've met the man, he's been an absolute gentleman."
A spokesperson for Pistorius at Fast Track in London said Pistorius is "assisting the police with their investigation, but there will be no further comment until matters become clearer."
The National Prosecuting Authority (NPA) said a court hearing for Pistorius, who is in jail, will be Friday at 9 a.m. local time.
Pistorius, a sprinter, had double below-the-knee amputations and a part of his legs has been replaced with carbon fiber blades. In 2012, he became the first double-leg amputee to participate in the Olympics, competing in the men's 400-meter race.
Steenkamp, according to her Twitter bio, is a law graduate and model. She tweeted Wednesday, "What do you have up your sleeve for your love tomorrow??? #getexcited #ValentinesDay." She recently appeared on the cover of FHM magazine, in commercials and was due to appear on a reality-TV show, "Tropika Island of Treasure."