South African platinum workers strike over pay
Work has stopped at some of the world's biggest platinum mines, as thousands of South African workers have gone on strike demanding a huge pay rise.
This is the biggest industrial unrest in South Africa's platinum sector since the 2012 Marikana massacre, when police shot dead 34 striking miners.
Unlike 2012, the current strike is legal.
A separate strike in the gold sector also planned for Thursday has been postponed following a court ruling.
Judge Hamilton Cele said that a decision on whether the protest by the Association of Mineworkers and Construction Union (Amcu) was "protected" - enabling workers to down tools without being dismissed or disciplined - would be taken on 30 January.
However, Amcu officials say that 70,000 of its members in the platinum sector will strike indefinitely.
The BBC's Milton Nkosi in Johannesburg says that the union is demanding a "living wage" - of about 12,500 rand ($1,200; £690) a month - more than double the workers' current pay.
Our correspondent says that most of the people taking part in the strike work deep underground as rock drill operators.
The world's three biggest platinum producers - Anglo American Platinum (Amplats), Impala Platinum (Implats) and Lonmin Platinum - have confirmed receiving official notices of strike action by Amcu.
Reuters news agency says Amplats has reported low attendance, while Implats has closed all its mines for safety reasons.
The mining companies insist that they cannot afford the pay increases because of high production costs and low demand.
A new law has made it illegal to carry dangerous weapons such as knobkerries (clubs), machetes and spears at public gatherings and protests.
The police involved in the 2012 Marikana unrest said they opened fire after being threatened by strikers carrying such weapons, as well as firearms.
Striking workers often carry traditional weapons at protests but correspondents say they are rarely used.
Amcu replaced the National Union of Mineworkers (Num) as the biggest union in the platinum sector during the Marikana protests.
Mineworkers have criticised the Num, which is affiliated with the governing African National Congress, saying it is too friendly with business.
As President Jacob Zuma and the ANC prepare for elections due in April, he is under pressure to tackle poverty.
The party was sharply criticised for not doing enough to prevent the Marikana massacre.
Former ANC youth leader Julius Malema has formed a new party which wants to nationalise the country's mines.
South Africa holds about 80% of the world's known platinum reserves and is the fourth-biggest gold exporter.