The owner of a South African platinum mine has softened its demands for striking workers to return to the job, saying those who fail to report Tuesday will be punished, but not necessarily fired.

Lonmin PLC had originally told workers to return Monday or face dismissal, but extended the deadline to Tuesday in light of deadly violence at its Marikana mine.

The company's executive vice president, Mark Munroe, told a radio station Tuesday that firing workers would be a setback in terms of violence and building trust.

The company says about 33 percent of workers reported Tuesday morning, up from 30 percent Monday.

Police killed 34 people at the mine last week after opening fire on striking workers. Ten people were killed in earlier incidents at the site.

Some 3,000 rock drill operators launched the strike August 10 to demand higher wages. Others have stayed away from the mine to avoid violence.

President Jacob Zuma has ordered a national week of mourning that began Monday to remember the lives of all South Africans who died violently, especially the 44 killed at the mine.

Lonmin is the world's third-largest platinum producer.