At least a thousand soldiers were deployed in Marikana on Saturday evening, the SA Defence Force (SANDF) said.
"The soldiers were deployed at the request of the police to support them in their operation,' said SANDF spokesman Brigadier General Xolani Mabanga.
Mabanga said the soldiers sent to Marikana included members from the air force, the army, and the military health services.
Earlier on Saturday, police fired rubber bullets to disperse striking mineworkers who had gathered in Nkaneng informal settlement in Wonderkop.
Twelve people were arrested during a raid at Lonmin mine's Karee hostel, and pangas, knobkerries and other dangerous weapons were seized.