The weekend killing of a senior member of the National Union of Mineworkers in Northam, Limpopo, triggered a wave of violence that forced Northam Platinum to shut its mine. The company stopped sending employees underground on Sunday night as a result of heightened tension after the man was shot dead on Sunday afternoon, CEO Paul Dunne said.A second person was stabbed to death during clashes between NUM and rival Association of Mineworkers and Construction Union groups in the area yesterday, police spokesman Ronel Otto said.Police fired rubber bullets to disperse the two groups.The NUM is the dominant union at he Zondereinde mine, which employs 7,000 people.Mine management and the police were due to meet the leadership of both the NUM and Amcu last night to explore ways to calm tensions, Dunne said.Mine management is wary of violence breaking out in communities around its mines and among its employees.Managers fear a repeat of the wildcat strike at Lonmin in 2012 that resulted in the deaths of more than 40 people, 34 of them shot dead by police during a protest in August of that year.Amcu president Joseph Mathunjwa told Reuters that the situation was "not as normal as one would hope".The NUM said it was "deeply hurt" by the killing of its member. ..