"We are not safe. Our phones have been tapped," the Association of Mineworkers and Construction Union president Joseph Mathenjwa told a crowd in the Wonderkop informal settlement at the Lonmin platinum mine.

"We have been democratically colonised - workers work under very harsh conditions."

On Thursday, 34 people were killed when the police opened fire on strikers, some of them armed, when trying to disperse them after a week of violent protests.

Another 10 people, including two policemen and two security guards, were killed in violence at the mine in the week before. The police ministry said 78 people were injured and 259 arrested during Thursday's shooting.

Mathenjwa accused the National Union of Mineworkers (NUM) and Lonmin of trying to get the striking workers fired.

"They will then together analyse and draw up a list. Any Amcu member will then be fired," he claimed.

"No worker should be fired until we are done with the counselling, burials and arbitration so that workers should stop suffering under the present conditions."

Mathenjwa said Amcu had no political affiliation.

"Amcu's politics is that about workers' conditions. We are not affiliated to any [political] party."

A delegation of opposition party leaders arrived in Marikana on Monday to address residents. It was led by the Congress of the People president Mosiuoa Lekota. He was joined by Democratic Alliance MP Wilmot James, United Democratic Movement leader Bantu Holomisa, and African Christian Democratic Party leader Kenneth Meshoe.

The leaders were expected to address the crowd later.

Lekota said he and his counterparts would meet Lonmin management and the two labour unions involved.

Xhosa king, chief Kumkani Ndamase II, who travelled from the Eastern Cape, told locals he was saddened by what happened, and hoped for peace.

The protests were believed to be linked to rivalry between NUM and Amcu over recognition agreements at the mine. Workers also wanted higher pay.