Pistorius Case: Lead Investigator Resigns
PHOTO: Olympic sprinter Oscar Pistorius, left, and police Detective Hilton Botha, are shown in court, Feb. 20, 2013 at the Magistrate Court in Pretoria, South Africa.

Credit: Stephane De Sakutin/AFP/Getty Images

ABC News' Liezl Thom reports:

Warrant Officer Hilton Botha, the former lead investigator in the murder case against Olympian Oscar Pistorius, has resigned from the South African Police Service, several weeks after he was removed from the case.

The police service called Botha's resignation a loss, but said it would in no way affect the investigation into the death of Reeva Steenkamp, Pistorius' girlfriend.

Steenkamp was shot and killed on Valentine's Day by Pistorius, whom she had been dating since November. Pistorius claims he mistook her for an intruder when he fired four shots through a locked bathroom door.

Botha testified at Pistorius' bail hearing and, during cross-examination, admitted to several mistakes by police. A day later it was revealed that Botha himself faced charges of attempted murder, stemming from an incident two years ago in which he allegedly fired at a taxi loaded filled with passengers while in pursuit of a suspect. The charges against him had been dropped but were reinstated earlier this year.

READ: Oscar Pistorius' Home, Where Girlfriend Was Fatally Shot, May Be Evidence in the Trial

The revelation prompted National Police Commissioner Riah Phiyega to remove Botha from the case and appoint a new team of investigators.

A police spokesperson, Brig. Neville Malila, said the investigation against Botha continues and he will be back in court in May. Malila said losing a detective with Botha's experience is a blow for the fight against crime in South Africa.

Meanwhile, Botha may still be called to testify in Pistorius' trial. Since he was the first police officer on the scene, the prosecution might subpoena him to appear in court as a state witness.

Pistorius was released on a R1 million bail (about $113,000) and has been saying with his uncle Arnold in the affluent suburb of Waterkloof, Pretoria. As part of his bail conditions, he may not return to his own house in the Silver Woods security estate. The house be kept exactly the way it was after the February 14 shooting, as it may form part of the state's evidence.

Pistorius is due back in court again in June, but it is unlikely that the trial will start before the last quarter of the year. Prosecutors could ask for another postponement when the case resumes. They will only serve an indictment on Pistorius, which will outline the exact charges against him, when they are confident they have all the evidence they would need to secure a conviction. A trial date will only be determined once the indictment has been served.

At the moment, Pistorius, the amputee athlete dubbed the "Blade Runner," stands accused of premeditated murder, but authorities have already indicated that at least one other charge, relating to the possession of unlicensed ammunition, will be added to the charge sheet.

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