A group of almost 60 striking coal miners were arrested Tuesday after a raid to demand higher wages at a South African coal mine owned by Glencore (LON:GLEN) turned violent.

The Association of Mineworkers and Construction Union (AMCU) said armed security guards fired at workers to dissolve picketing lines. But Reuters reports strikers are the ones who have made of the labour action a violent one, with AMCU members intimidating other employees and damaging nearby farms and other private property.

Production at the Wonderfontein coal mine has been halted for three weeks after members of AMCU decided to down tools in March. They are demanding their basic monthly salary to be doubled from about $265 (R4,000) to $530 (R8,000), as well as medical aid, transport and housing allowances.

“While the first week of the strike was fairly peaceful, it has turned increasingly violent in the past two weeks, resulting in the obtaining of a court order against AMCU and its members to desist from acts of violence at the mine,” Glencore said in a statement quoted by Reuters.

The union said through its Twitter feed that leaders would meet mine representatives later today following today’s violent incident.

AMCU also plans a strike due to start on Wednesday at Sibanye Gold (JSE:SGL) (NYSE:SBGL) to demand higher wages.

GLENCORE rejected claims by the Association of Mineworkers & Construction Union (AMCU) that the mining group ordered security officials open fire on its members engaged in strike protest at the 3.2 million tonne a year Wonderfontein coal mine in South Africa’s Mpumalanga province.

Wonderfontein Coal mine is a joint venture between Glencore and Shanduka Group.(Source: Mining.com)