Johannesburg - Police should not be "peace brokers", they said following a massacre at the Marikana mine in which more than 30 people were killed.
Police ministry spokesperson Zweli Mnisi said police figures indicated that "over 30" people were killed in Thursday's shoot-out at the mine in the North West, which he described as "a tragedy".
He said that the official body count could rise as more information emerged.
Mnisi said police were called in to maintain order after the violent protests claimed the lives of 10 people, two of them police officers, in the past week.
"This cannot be a policing matter.... We are coming to a point where we have labour matters that police cannot resolve," he said.
Union leaders and mine management should have met to defuse tensions and prevent the bloodshed.
"Police should not be peace brokers. We cannot resolve labour matters. Where was the voice of unions and management?" Mnisi asked.
‘Peaceful protests planned properly’
Mnisi said the workers had a constitutional right to protest "but [the Constitution] does not say you have a right to be violent when you protest".
The strikers should have involved the police when planning their protests, as a security plan could have averted the trouble.
"There are so many peaceful protests that are properly planned," he said.
Mnisi said that the Independent Police Investigative Directorate was on the scene, and that a full investigation was underway.
Meanwhile, the National Union of Mineworkers says the death toll has risen to 36.
"Our shopstewards on the ground report that 36 people were killed," said National Union of Mineworkers (NUM) general secretary Frans Baleni.
"We are extremely saddened by this loss of life, it could have been avoided."
The protests, which began last Friday, are believed to be linked to rivalry between the NUM and the Association of Mineworkers and Construction Union over recognition agreements at the mine. Workers also wanted higher wages.