South Africa's top mineworkers union has accused a rival of using witchcraft to boost recruiting, an allegation taken seriously among the rank and file in a country where traditional spiritual beliefs are widely held.South Africa's National Union of Mineworkers (NUM) has been locked in a violent battle for membership with the upstart Association of Mineworkers and Construction Union (AMCU) at the world's largest platinum mine, run by Impala Platinum."One of the tools which is used strongly is 'muti'," NUM General Secretary Frans Baleni told journalists on Thursday night, referring to traditional medicines that can be made from a range of ingredients including animal or human body parts.Baleni said NUM's members believed that AMCU had a "very strong 'sangoma'," or witch doctor."One of the myths is that if you don't toe the line, especially if you are a man, if you defy them you might have bedroom problems at home," he said.Sangomas are widely respected by South Africans of all walks of life, including business leaders and politicians.Baleni later told Reuters it was an issue that was not being taken lightly because many workers believed in such things."We are taking it seriously as part of the tactics of this union as our members are telling us about the use of sangomas and muti," Baleni said.AMCU officials said they were not using witchcraft."There is no one among us who is using muti or sangomas. It is rubbish that he is saying. We uphold Christian principles, we don't use sangomas," said AMCU General Secretary Jeff Mphahlehle.NUM has also accused AMCU of using violence to recruit, which it has denied.