(CNN) -- Violence between competing unions at South Africa's mines is threatening to weaken Africa's largest economy. On Wednesday, the world's top platinum producer, Anglo American, suspended all of its operations in Rustenburg, South Africa due to "intimidation" of its workers. Striking workers are also halting operations at some gold mines. The move follows strike-related violence at Lonmin's Marikana mine in August that left 44 dead. What triggered the violence? The 34 miners in the Lonmin mine in Marikana, South Africa, died after police opened fire on a gathering of thousands of machete-armed workers striking for higher wages. The shootings came after deaths earlier in the week, including those of two police officers who were hacked to death. The violence exploded when police shot at striking rock drillers in the "Easterns" area of the Marikana mine. Tensions have been high in part because of the presence of competing trade unions, the Association of Mineworkers and Construction Union (AMCU) and the National Union of Mineworkers (NUM).
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More than 30 miners died after police opened fire on striking workers who were armed with machetes
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Rivalry between the AMCU and the NUM is widely blamed for feeding the violence
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The two implicated unions denied instigating the clashes, and are blaming others for the violence
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President Jacob Zuma, of the country's ruling African National Congress, has announced an inquiry into the violence
The AMCU, which has expanded rapidly this year at the expense of @placeholder, is seen as the more militant union and has been linked to aggressive tactics to win wage increases.