Violence at the Impala Platinum (Implats) mine in Rustenburg looks set to escalate after the National Union of Mineworkers (NUM) threatened yesterday to take the law into its own hands and defend its members against the rival Association of Mineworkers and Construction Union (AMCU).

NUM has reportedly lost thousands of members to the AMCU, a move that has sparked violence that has claimed lives of many workers.

The Rustenburg mine remained closed for a second day yesterday, taking another 3 000 ounces out of global output, as the union turf war rumbled on. Implats said it was applying for a court interdict but was confident of getting miners to return to work soon.

“The rival unions are still playing a game of winner takes all. This should not be a fight to the death,” Johan Theron, the head of human resources at Implats, said.

The flare-up dashes hopes of finally settling a labour battle that shut the mine, which accounts for about 15 percent of global output, for six weeks earlier this year. That cost Implats 120 000 ounces in lost production.

The latest fracas was sparked when, according to police, suspected AMCU supporters allegedly shot and wounded a NUM member last week. Their arrest on Monday prompted protests, which saw most of the mine’s workforce failing to report for duty on Tuesday.

Theron said the AMCU, which has launched a recruiting drive, wanted recognition from the company and now claimed to have 10 000 members, or about a third of the 30 000-strong labour force if processing workers are counted.

He said about a third of the workers were not union members, so if the AMCU’s claims were true, its numbers at the operation would now roughly equal those of NUM.

Theron said the company planned to conduct an audit of the workforce and if this was true, it would have to renegotiate its “majority union” agreement with NUM.

NUM launched a four-day congress yesterday where the AMCU challenge was discussed.

Senzeni Zokwana, the president of NUM, told the congress that members would defend themselves against violence.

“If police continue to fail us, we will be left with no other choice but to defend ourselves,” he said.

Zokwana blamed the police and Implats for sympathising with AMCU.

The stakes are high as AMCU is widely regarded to be more radical than NUM, which has managed to consistently secure above-inflation wage increases for its members.

Platinum producers negotiate their contracts with workers separately, making them more vulnerable to recruitment drives from new unions than their gold or coal counterparts, which do so collectively as an industry through the Chamber of Mines.

NUM is considering calling for help from Cosatu, of which it is an affiliate and which has proved to be very influential. It also wants to ask the government to revoke Implats’ mining licence for failing to protect the worker who was shot.

Department of Mineral Resources spokeswoman Zingaphi Jakuja said the matter was an operational issue that should be addressed by mine management, not the department. “Of course, in the interest of the sector, the department would want to see efficiently operating mines, compliant with their respective licence and rights conditions.”

Theron said there was no basis for the government to revoke Implats’ licence.

Rivalry between the two unions and concern about pay disparity led to the dismissal of 17 200 Rustenburg workers during an illegal strike that shut operations at Rustenburg from January 20 to March 5. Four people were killed and more than 50 were injured during the protest. Most of the workers were later reinstated.

Another platinum producer in the area, Lonmin, has also been affected by the violence.

Taula Dolane, 55, died after being assaulted on his way to Lonmin’s Karee mine. He was among a dozen Lonmin employees who were reportedly intimidated and assaulted last month.

Andrew Levy, a labour economist, said inter-union rivalry was often started by a “grievance union”. These unions had no real influence, but sowed discord by saying that the existing union was useless.

Dumisani Nkalitshana, the national organiser at AMCU, denied allegations that the union was responsible for sowing division.

“If NUM is losing membership, they must not lie and blame us. They are just running away from their problem.”

AMCU signed a recognition agreement at Lonmin’s Karee mine two weeks ago.

Ian Farmer, the chief executive of Lonmin, said this week that 3 600 employees, or a third of the mine’s staff, were AMCU members, another third were with NUM and the rest were not represented by unions.