South African police opened fire Thursday on a crowd of striking workers at a platinum mine, leaving an unknown number of people injured and possibly dead. Motionless bodies lay on the ground in pools of blood.

Police moved in on striking workers who gathered near the Lonmin PLC mine, located 70 kilometres northwest of Johannesburg, on Thursday afternoon after urging them to give up their weapons and go home to their hostels and shacks.

Some did leave, though others carrying weapons began war chants and soon started marching toward the township near the mine, said Molaole Montsho, a journalist with the South African Press Association who was at the scene.

The police opened up with a water cannon first, then used stun grenades and tear gas to try and break up the crowd, Montsho said.

Suddenly, a group of miners rushed through the scrub and underbrush at a line of police officers. Images broadcast by private television broadcaster e.tv showed officers immediately opening fire, with miners falling to the ground. Dozens of shots were fired by police armed with automatic rifles and pistols.

The gunfire from weapons apparently on full automatic ended with police officers shouting: "Cease fire!" By that time, bodies were lying in the dust, some pouring blood. Another image showed some miners, their eyes wide, looking in the distance at heavily armed police officers in riot gear.

It was an astonishing development in a country that has been a model of stability since racist white rule ended with South Africa's first all-race elections in 1994.

The unrest at the Lonmin mine began Aug. 10, as some 3,000 workers walked off the job over wages, in what management described as an illegal strike. Lonmin is the world's third largest platinum producer. Amid the unrest, global platinum values rose more than $30 an ounce in trading Thursday while stock in Lonmin plunged 6.76 per cent on the London Stock Exchange. The company's stock value has dropped more than 12 per cent since the start of the strike.

Several others killed previously

Lonmin announced Thursday its CEO Ian Farmer has been diagnosed with a serious illness and has been hospitalized. It did not disclose Farmer's illness.

Police Capt. Dennis Adriao, a spokesman for the officers at the mine, declined to immediately comment. Jeff Wicks, a spokesman for private ambulance company Netcare Ltd. that was standing by at the mine, also declined to comment.

Barnard O. Mokwena, an executive vice-president at Lonmin, would say only: "It's a police operation."

In a statement earlier Thursday, Lonmin had said striking workers would be sacked if they did not appear at their shifts Friday.

Police surround the bodies of striking miners after opening fire on a crowd at the Lonmin Platinum Mine near Rustenburg, South Africa. (Associated Press)

"The striking [workers] remain armed and away from work," the statement read. "This is illegal."

Those who tried to go to work on Saturday were attacked, management and the National Union of Mineworkers said.

On Sunday, the rage became deadly as a crowd killed two security guards by setting their car ablaze, authorities said. By Monday, angry mobs killed two other workers and overpowered police, killing two officers, officials said. Officers opened fire that day, killing three others, police said.

On Tuesday and Wednesday, thousands of miners had gathered at a rocky cliff within sight of the mine's smelter. They cheered, sang and marched around with machetes and clubs under the watchful eye of police officers in armoured trucks. Some leaders of the miners spoke with the police and largely followed their instructions, breaking up the protest as dusk fell.

Operations at Lonmin appeared to come to a standstill Tuesday as workers stayed away from the mines, where 96 per cent of all Lonmin's platinum production comes from. The stoppage also has spooked those investing in Lonmin.

While the walkout appeared to be about wages, the ensuing violence has been fuelled by the struggles between the dominant National Union of Mineworkers and the upstart Association of Mineworkers and Construction Union. Disputes between the two unions escalated into violence earlier this year at another mine.