Russel Morena and Ntwaagae Seleka
The prosecution plans to bring more charges after reports that witnesses are being intimidated in a case in which two policemen face charges of extortion, fraud and corruption.
The policemen, based in Booysens, Johannesburg, also face charges of defeating the ends of justice and of intimidation.
One key witness has been killed in an execution-style shooting and another is in hiding after she was threatened.
The witness received a call from an unknown man who warned her not to testify against inspectors Sean Thwala and Tello Mota.
The policemen appeared before magistrate Ashika Ramlaal in the Johannesburg magistrate's court yesterday. They also face a charge of theft.
State prosecutor Freda Mudaly asked for a postponement and said four more charges were being investigated against the policemen.
Mudaly said the state was awaiting the availability of witnesses before adding the charges.
"More charges could be added against the accused, depending on the availability of witnesses to testify against them," Mudaly said.
Lindiwe Mthembu, 37, who was expected to testify against Thwala and Mota, was gunned down at her flat in Hillbrow on Thursday by unknown killers. She was shot several times.
She was killed on the stairs of the block of flats where she lived.
Mthembu was a member of a committee of flat dwellers fighting crime, theft and corruption.
Thwala and Mota were arrested in September 2006 after police received complaints about policemen allegedly extorting money from tenants in buildings in Johannesburg, and selling impounded cars.
Mthembu's husband Petros, who was in church at the time of the shooting, found his wife's body four hours after the shooting. He said two other witnesses had gone into hiding after receiving death threats.
The case was postponed to March 4 for a plea and trial.