Five suspects, of whom four are women, have been arrested for the murder of Prince Lethukuthula Zulu, the first-born son of King Goodwill Zwelithini kaBhekuzulu.
Prince Lethukuthula Zulu's body was found by security guards at his place of residence in the Graceland residential complex, Northworld, on 6 November.
At the time, the police said the information was still sketchy, and a probe was underway to find out the circumstances that led to the death of the 50-year-old.
News24 reported an inquest docket had been opened for further investigation at the Honeydew police station and the guards also found the deceased's friend sleeping in another bedroom.
On Sunday, police spokesperson Brigadier Mathapelo Peters announced a breakthrough had been made in the case following meticulous investigation and hard work by the provincial investigating team.
The piecing together of information saw the inquest being changed to a murder case.
"Critical evidence that could easily have been overlooked was effectively lifted from the crime scene by police forensic science experts," Peters said in a statement.
"The processed evidence assisted the investigating team in establishing a possible linkage of the suspects to the crime."
On Friday evening, the five suspects were arrested. Four women between the ages of 27 and 42 as well as a 32-year old man were apprehended in Pretoria.
Peters added during the arrest, one of the suspects was found in possession of different substances that were seized for further investigation.
There is a possibility the substances were used to drug the prince and his business partner before cash and other valuables were stolen from his house.
"Several suspected stolen items were seized at the residences of the suspects.
"The investigation continues as the police envisage to possibly uncover more evidence towards building a solid case that can stand in court."
Peters said the investigation would look into whether the suspects could have committed similar crimes where victims were drugged and robbed.
The police have not yet revealed how the prince might have been murdered, but Peters previously said a post-mortem would be conducted to determine the exact cause of death.
The suspects will appear in the Randburg Magistrate's Court on Monday on charges of murder and theft.