Oscar Pistorius, the Olympic track star who wowed us at the Summer Games as the first Olympian to compete without legs, has been arrested in South Africa and charged with the murder of his girlfriend.

Authorities believe that Pistorius shot Reeva Steenkamp, his 30-year-old aspiring model girlfriend, in the hand and the head with a 9 millimeter pistol. South African media outlets are reporting that Steenkamp was trying to surprise Pistorius for Valentine's Day, but he thought she was a burglar and fired at her. Police are investigating that claim, but also noted that there have been "previous incidents" of domestic disturbances reported at Pistorius' home.

The 26-year-old got the name "Blade Runner" for his use of prosthetic blades made of carbon fiber.

Following his arrest, the ad that Nike built around him that reads, "I am a bullet in the chamber" was pulled from his website. The slogan referred to Pistorius' quick starts in his races, but now has another unfortunate connection.

Sources: Los Angeles Times, Chicago Tribune