Employees of Anglo American Platinum in Rustenburg and Pilanesberg north returned to work on Thursday after striking a new wage deal.
This on Monday during a clash between security guards and workers, say North West police.
"Some of the people were hacked with pangas and sharp objects, while others were shot with security rubber bullets," Brigadier Thulani Ngubane said.
"A group of about 1 000 strong … attacked four people who were at the union offices. Mine security intervened and fired rubber bullets, and in the process a total of 13 mine workers, including four security guards, [were injured]."
He said the injured people were admitted to Bleskop Hospital.
Ngubane said four National Union of Mineworkers' (NUM) shop stewards arrived at the mine premises to reclaim occupancy of union offices.
Animosity
"Allegations further state that other mineworkers of Amcu [Association of Mineworkers and Construction Union] were not happy with their return," he said.
"It is alleged that the mineworkers who were not happy complained to the management and demanded that the four workers must be sent back home."
He said NUM members survived by "running for their lives" and hiding in the union's offices.
No deaths have been reported at this stage, Ngubane said.
Anglo American Platinum (Amplats) spokesperson Mpumi Sithole confirmed the clash and said members of the workers' committee were contesting "NUM's legitimacy at the mine, and were demanding that NUM vacate its offices".
"The company is currently in the process of validating union membership at Rustenburg and the mines north of the Pilanesberg," she said in a statement.
Strikes
"Anglo American Platinum expresses its deep concern about this incident and appeals for its employees to remain calm and respect the company's dispute resolution process."
Ngubane said the police were investigating cases of public violence, attempted murder and assault with intent to cause grievous bodily harm.
Earlier, the Amplats Workers' Committee said five NUM members were shot.
One of them was shot in the head, the committee said.
In August last year, Amplats fired 12 000 strikers from its Rustenburg operation.
The workers were later taken back.
They had gone on a wildcat strike, demanding a R16 000 salary before deductions.
In January, workers at three of Amplats' operations went on strike hours after the company announced plans to mothball shafts and cut 14 000 jobs.
Amplats lost R3.4-billion in revenue when production ground to a halt in mid-September. – Sapa