Updated

South African Olympic sprinter Oscar Pistorius has reportedly been charged with shooting and killing his girlfriend in what may have been a tragic accident.

According to reports in Johannesburg, including Talk Radio 702, Pistorius shot Reeva Steenkamp early Thursday morning at the runner's home in a suburb of Johannesburg.

Various reports indicate Pistorius may have mistaken her for a burglar. She apparently entered Pistorius' home at around 4 or 5 a.m., local time. There has been speculation that Steenkamp might have been trying to surprise Pistorius for Valentine's Day.

Steenkamp, a model who was 30 years old, had written on her Twitter account that she was looking forward to Valentine's Day, writing "What do you have up your sleeve for your love tomorrow???"

Pistorius made history at the London Olympics last year when he became the first double-amputee runner to compete in the Games.