Czech citizen Radovan Krejcir has been charged with conspiracy to commit murder, police spokesperson Solomon Makgale said on Monday.
Krejcir was charged on Thursday and appeared in the Alexandra Magistrate's Court, Makgale said.
"This is linked to the arrests of suspects in January this year for the alleged conspiracy to murder Colonel [Nkosana "Killer"] Ximba of our National Crime Intelligence Unit and Mr Paul O'Sullivan," he said.
Five people have been arrested for allegedly attempting to murder investigators Ximba and O'Sullivan who were associated with Krejcir's investigation.
One of the men was also linked to the kidnapping and attempted murder case for which Krejcir is being investigated.
The kidnapping case allegedly involves Krejcir, Sandton businessperson Desai Luphondo, and two members of the Hawks – Warrant Officers Samuel Modise Maropeng and George Jeff Nthoroane. They were arrested in November.
In June, they allegedly kidnapped and assaulted a man whose brother, known only as "Doctor", disappeared with a 25kg shipment of tik he had been recruited to help smuggle through OR Tambo International Airport.
They allegedly kept the man at Krejcir's Money Point business in Bedfordview, Johannesburg, for four days, and assaulted him.
Krejir will appear in the Alexandra Magistrate's Court with five other people on April 7 on charges of conspiracy to commit murder.
"Investigations are continuing and more arrests are expected," said Makgale. – Sapa