Striking miners in South Africa could face the sack if they defy a union agreement to return to work for another day.
They have been given until Tuesday afternoon to return to work.
The bulk of the 3,000 members of the Association of Mineworkers and Construction Union (AMCU) - who led the so-called wildcat strike - have continued their protest.
"There must be a national strike. They have been stealing this gold from you. Now it is your turn. You want your piece of gold. These people are making billions from these mines."
- Julius Malema, Ex-ANC youth leader
South Africa's labour mediation committee has extended the deadline to Tuesday for workers at the world's third largest platinum mine to return to work in order for salary negotiations to start.
The workers, who have been on strike for a month, have vowed to stay off the job until they receive wages of $1,500 a month, double what they now earn.
The committee says its "facilitation is dependent on a return to work by all workers" and threatened to leave the miners to deal with Lonmin managers.
Only about 1,700 workers clocked in for their shift on Monday while thousands marched for higher wages after the committee earlier issued a Monday deadline.
Hundreds of striking miners marched on Monday in defiance of the agreement signed by the mine management and the main National Union of Mineworkers (NUM).
Al Jazeera’s Mike Hanna, reporting from Marikana, said: "One group of miners continue to insist they will not return to work until an agreement is reached on increasing their wages."
"It’s once again one group of striking miners coming up against mine owners. No progress whatsoever in weeks of negotiations in a bid to end the strike," he said.
Tensions have been high at the mine since 34 of the protesting workers were shot and killed by police last month.
Meanwhile, firebrand politician Julius Malema has called for a national strike in all South African mines to demand the removal of the leadership of the NUM.
Thousands of striking miners at a gold mine in Driefontein blowing on vuvuzelas, whistles, and carrying traditional sticks responded enthusiastically to Malema's comments on Tuesday.
"There must be a national strike. They have been stealing this gold from you. Now it is your turn. You want your piece of gold. These people are making billions from these mines," Malema said, referring to black elite and the white minority that controls the economy.
"What you must do, you just put down the tools and stop production."
Frans Baleni, NUM general secretary, told Al Jazeera that a high level of intimidation has stopped many miners from returning to work.
"The workers are still scared. There have been threats that those who have reported for duty would have their homes torched," he said.
"Some of the workers also feel threatened by their managers. Peace has not really prevailed at this stage, which is the main reason why workers would stay away."
Separately, Al Jazeera has learned that some of the protesting miners who were shot dead at the Marikana mine last month may have been trying to surrender.
|Danny Titus, from the South African Human Rights Commission, discusses the Marikana shooting
A prominent human rights organisation in South Africa launched an independent investigation into the police shootings on Sunday.
The Legal Resource Centre (LRC) said that it had obtained multiple witness testimonies that blame police brutality for the killings of strikers who were calling for pay raises.
Some witnesses have said that police shot protesters who were either trying to escape confrontations with police by hiding behind rocks, or while surrendering to authorities.
The LRC also said it has forensic evidence that suggests a police cover-up of the killings.
Video showed a densely packed crowd of miners, some armed with clubs and machetes, approaching heavily armed police, who claimed self-defence in the shooting.
The incident was the climax of an escalating stand-off between rival unions that had already killed 10 people, including two police officers.
Government officials and police officers have repeatedly rejected Al Jazeera's request to comment on the allegations, saying they would not speculate until a judicial inquiry into the incident was complete.
The ongoing industrial action has pushed down Lonmin's shares, raised world platinum prices and fuelled fears of labour unrest spreading through the mining sector of Africa's largest economy.
Source: Al Jazeera and agencies