JOHANNESBURG, South Africa — Police have completed their murder investigation of double-amputee track star Oscar Pistorius, and the Blade Runner will appear in court next week to receive detailed charges for the Valentine’s Day shooting of his girlfriend.

Police said yesterday they had used forensic experts, ballistics experts, psychologists and technology experts to investigate the Feb. 14 death of Reeva Steenkamp, who was shot by Pistorius through a closed bathroom door.

Pistorius, 26, has admitted to firing four shots at Steenkamp. In pretrial testimony, Pistorius’s lawyers said the athlete was acting in self-defense against what he thought was an intruder.