Capturing the world's attention, the first day of testimony in the Oscar Pistorius murder trial took place in Pretoria, South Africa on Monday (March 3).

Before hearing from the first witness, the double amputee athlete pleaded not guilty to murder and some weapons-related charges.

Last year, the former Olympian shot his model girlfriend, Reeva Steenkamp in his residence. According to the Blade Runner, he thought she was a home intruder.

In the courtroom, witness Michelle Burger testified that she heard a woman screaming and a man yelling for help, saying, "Something terrible was happening at that house. Her shouts, her screams were petrifying." The trial is expected to last for weeks.