PRETORIA, South Africa -- The South African police replaced the lead investigator in the Oscar Pistorius homicide case Thursday after revelations that he was facing seven charges of attempted murder himself.
The decision by the national police commissioner to remove the investigator, Warrant Officer Detective Hilton Botha, was the latest in a series of abrupt twists and setbacks in the prosecution of Mr. Pistorius, the double amputee Olympic track star accused of murdering his girlfriend Feb. 14 by firing four shots through a locked bathroom door while she was on the other side.
Riah Phiyega, the commissioner, said at a news conference that a divisional police commissioner, Lt. Gen. Vinesh Moonoo, would be assigned to preside over "this very important investigation."
After widespread media reports about the charges against Detective Botha, prosecutor Gerrie Nel said at the start of the hearing Thursday that he had just learned about them. The news only compounded questions about Detective Botha's work on the Pistorius case. Under cross-examination Wednesday, he was forced to acknowledge several mistakes in the investigation, and to concede that he could not rule out Mr. Pistorius' version of events based on the existing evidence.
While the prosecution has accused Mr. Pistorius, 26, of premeditated murder, Mr. Pistorius has said he opened fire through the door thinking there was an intruder in his home, located in a gated community in Pretoria, and had no intention of killing his girlfriend, Reeva Steenkamp, 29, a model and law school graduate.
"The poor quality of evidence presented by chief investigating officer Botha exposed the disastrous shortcomings in the state's case," Mr. Pistorius' defense lawyer, Barry Roux, said Thursday.
Mr. Nel tried to regain some of the ground lost Wednesday, arguing that no matter who Mr. Pistorius thought was behind the bathroom door, the fact that he shot the person constituted murder. "What we can't forget is the applicant is charged with murdering a defenseless, innocent woman," he said.
Mr. Nel repeatedly questioned Mr. Pistorius' version of events. Mr. Pistorius has said he did not realize that Ms. Steenkamp was no longer in bed as he rose to investigate the supposed intruder, shouting to her to call the police.
"You want to protect her, but you don't even look at her?" Mr. Nel said. "You don't even ask, 'Reeva, are you all right?' " He asked how Mr. Pistorius could have retrieved the 9mm pistol used in the shooting from under her side of the bed without noticing that she was gone. "His version is so improbable," the prosecutor said.
Another bit of drama rippled through the courtroom Thursday when the magistrate hearing the case ordered a brief suspension because of a "threat to the court," which turned out to be a fracas that had broken out outside the courtroom. The hearing continued a few minutes later and was later adjourned until today.
In a separate announcement to reporters Thursday, a police brigadier, Neville Malila, said Detective Botha was set to appear in court in May on the attempted murder charges, which stem from an episode in 2011 in which he and two other police officers fired at a minivan. "Botha and two other policemen allegedly tried to stop a minibus taxi with seven people," Mr. Malila said. "They fired shots."
While the charges were initially dropped, "we were informed yesterday that the charges will be reinstated," he said.
Medupe Simasiku, spokesman for the National Prosecuting Authority, told reporters that the decision to reinstate the charges was made Feb. 4, long before Ms. Steenkamp was killed. "It's completely unrelated to this trial," the spokesman said.