File picture: Supplied

Welkom - Two more suspects, aged 27 and 35, have been arrested for the murder of Harmony Gold manager Simphiwe Kubheka, police said on Monday.

Khubeka, 36, who was the regional manager of the third largest gold mining company in South Africa, was shot dead in his car on Thursday last week.

Police spokesperson Brigadier Motantsi Makhele said the two suspects were arrested on Sunday. 

A third suspect, Lehlohonolo Thethe, 25, appeared in court on Monday. He was arrested on Friday. 

"Kubheka left Tshepong mine driving in his vehicle when he was shot. He sustained two gunshot wounds, on the head and on the right arm,
and was declared dead on the scene", Makhele said.

There has been speculation that he was murdered by illegal miners.

All three suspects are expected to appear in the Welkom Magistrate's Court on Wednesday.