One of the world's largest platinum mines in back is operation after a strike, its owner announced Monday, following police violence last week that left 34 workers dead.

But production levels are "insignificant," Lonmin executive vice president Mark Munroe said at a news conference after the announcement.

"To all intents and purposes, we are not producing ore," he said, acknowledging that the company will not meet platinum production targets for the year.

The mood at the mine was "stable but tense" Monday, police said, after a strike over pay that has been marked by terrible violence.

About 3,000 drillers and assistant drillers at the mine in South Africa went on strike on August 10.

The miners, who earn $300 to $500 a month, want their salaries raised to $1,500 a month.

Lonmin, the world's third-largest producer of platinum, said no to the increase and called the strike illegal.

Almost a third of the workers at the Lonmin mine came to work Monday, the company-imposed deadline for strikers to return to their jobs.

Munroe, the company executive, said Lonmin believed that most of the workers who stayed away had been intimidated, not because they were on strike.

The company withdrew a threat to fire workers who did not come to work Monday, it said, following meetings with union representatives, and gave the striking workers an extra day to return.

Last week, police fired on striking miners, killing 34 workers and wounding 78. They also arrested 259 on various charges, including malicious damage to property, armed robbery, illegal gathering and possession of weapons.

Police Commissioner Riah Phiyega has said police "were forced to utilize maximum force to defend themselves."

An executive with the Solidarity union Monday blamed violent protests at the mine on "opportunists" exploiting the strike.

"The protestors' violent behavior, the brutal murders of innocent people and the use of witch doctors and traditional murder weapons rather indicate a political motivation and opportunistic positioning instead of an attempt to negotiate a solution," said Gideon du Plessis, deputy general secretary of Solidarity.

The striking rock drill operators belong to another union called AMCU.

Lonmin said Sunday it was telling nonstriking workers that "police consider it safe to report for duty again" Monday morning and was ordering strikers to go back to work or face possible dismissals.

Facing the ultimatum, one South African drill operator told CNN that he and his co-workers should honor their slain colleagues and hold out for a pay increase.

"Otherwise, they will have died in vain," Cingisile Makhaba said Sunday.

Cyril Ramaphosa, an African National Congress executive committee member who owns shares in the mine, is donating $250,000 to pay for the funerals of those killed last week.

But Makhaba said the money is "of no use now. It won't bring back the dead."

"Where is this money coming from?" he asked. "They should have used it to increase our wages."

Makhaba lives with his two children in a compound of one-room shacks he shares with eight other families.

"We work hard, but we live like animals," he said.

Over the weekend, thousands of people gathered outside the platinum mine in anger over the shooting.

The situation was calm but tense as police stood near the protest Saturday and helicopters conducted surveillance.