The Police Commissioner, Riah Phiyega, said her officers had no choice but to use ''maximum force'' against charging protesters at Marikana platinum mine, about 96 kilometres north-west of Johannesburg.

Critics accused the police of turning a protest into ''a kill zone'', while a trade union leader said there was ''no need'' for such bloodshed.

Yesterday, sobbing women were searching for their missing husbands near the mine, owned by Lonmin, a London-listed company. Police said 78 miners were wounded - some critically - when a rank of officers opened fire with automatic weapons on Thursday.

''I didn't see my husband since yesterday morning,'' a weeping woman with a baby on her back said. Neither the police nor the Lonmin mine hospital, where the wounded were being treated, were prepared to help, she added.

Poloko Tau, a journalist, accused the police of making a ''well-planned attack that turned a protest into a kill zone''. He added: ''No one, not the unions, the protesters on the hill, or the journalists at the scene expected the mayhem that followed.''

The President, Jacob Zuma, left a regional summit in Mozambique and flew back to South Africa as the nation absorbed an event that brought memories of apartheid-era bloodshed, notably the Sharpeville massacre of 1960.

Mr Zuma ordered an official inquiry, adding: ''We have to uncover the truth about what happened here.''

The President said: ''This is not a day to apportion blame. It is a day for us to mourn together as a nation.''

Almost two decades after the end of white rule, the anger and resentment of South Africa's impoverished black majority is steadily rising. ''African lives are cheap as ever,'' an editorial in the Sowetan said.

In a normal country, the paper said, the bloodshed ''would have led to drastic measures being taken by the government''. But ''this is an abnormal country in which all the fancy laws are enacted and the constitution is hailed as the best on earth. All the right noises are made and yet the value of human life, especially that of the African, continues to be meaningless.''

A radical union, the Association of Mineworkers and Construction Union, organised the strike at Marikana mine.

The union's general secretary, Jeffrey Mphahlele, accused the police of overreacting. He said: ''There was no need whatsoever for these people to be killed like that.''

Ms Phiyega gave a detailed account of events leading up to the shooting. Miners at Marikana were divided between those striking for higher pay, and others who tried to continue as normal.

This reflected a poisonous rivalry between the National Union of Mineworkers, a long-established body, and the newly created AMCU.

Fighting between the miners claimed three lives last week and two policemen were hacked to death on Monday. Police told the miners to lay down their arms - which included guns, clubs and machetes - and reach a negotiated settlement. On Thursday, though, about 3000 miners - many of them armed - defied this order by massing near Marikana. Police tried to break them up to make them ''more manageable'', but the miners charged. ''We tried to repel the advance with water cannon, tear gas and stun grenades,'' Ms Phiyega said.

Still the miners came forward: a vivid scene on television showed them charging at armed police. At this point, officers were ''forced to use maximum force to defend themselves'', the commissioner said.

Scores of miners were cut down, leaving dead and wounded strewn across the bush. Experts cautioned that it was too early to pass judgment. Johan Burger, of South Africa's Institute for Security Studies, said: ''We don't know enough yet, but we do know that some of the workers gathered on that hill were heavily armed and they shot at the police. We are checking to see whether they also shot at a helicopter.''

The platinum miners at Marikana are paid about $680 a month, and the strikers wanted Lonmin to double their salaries. Many have left behind wives and families in other parts of South Africa and neighbouring countries.

Telegraph, London