Johannesburg , South Africa ( CNN ) -- Nine mine employees were hurt Monday when Anglo American Platinum security guards shot rubber bullets to break up a confrontation between rival union groups at a mine in northwest South Africa , the company said in a statement . The incident occurred at the company 's Siphumelele mine in the Rustenburg area and involved members of the Workers Committee and shop stewards for the National Union of Mineworkers . `` As they were attempting to evacuate the NUM shop stewards who were trapped in their offices , three security personnel sustained minor injuries during this incident , '' the statement said . All 12 injured employees received medical attention ; none of the injuries was life-threatening , it added . Police spokesman Brig . Thulani Ngubane said those hurt were taken to Bleskop Hospital . The shootings did not involve police , he said . `` Workers committee members are contesting NUM 's legitimacy at the mine and demanding that NUM vacate its offices , '' the company statement said . The company said it is trying to validate union membership at Rustenburg and the mines north of the Pilanesberg National Park . Anglo American Platinum Limited , a member of the Anglo American plc Group , describes itself as the world 's leading primary producer of platinum group metals , accounting for 40 % of the world 's newly mined platinum . Its mining , smelting and refining operations are based in South Africa . Last fall , several major South African mining companies , including Anglo American , were involved in labor disputes with their miners that erupted in violence . In October , police repeatedly clashed with protesters near one of Anglo American 's mines , and the company fired about 12,000 striking workers who refused to attend disciplinary hearings . The union did not immediately respond to a request for comment . CNN 's Kim Norgaard reported on this story from Johannesburg , and Tom Watkins wrote it in Atlanta .
Nine employees were shot with rubber bullets , the company says . Three security personnel sustained minor injuries , it adds . Workers Committee members are contesting the legitimacy of the National Union of Mineworkers .