Police have fired rubber bullets and tear gas to disperse about 1,000 striking miners at a leading platinum mine in South Africa.
The workers had earlier torched an electricity sub-station and had set up barricades, police said.
The strikers have rejected a deal to return to work on Tuesday, saying their demand for higher pay should be met.
South Africa's mines have been hit by a series of wildcat strikes, which have cost millions of dollars.
More than 40 people died in August in clashes between police and striking workers at the Lonmin-owned Marikana platinum mine near Rustenburg, 120km (70 miles) north-west of Johannesburg.
The latest clashes took place at a mine owned in the same area by the world's biggest platinum producer, Anglo American Platinum (Amplats).
Over the weekend, Amplats had agreed to reinstate 12,000 miners sacked for taking part in a six-week-long unofficial strike.
Police spokesman Capt Dennis Adriao said the Khuseleka power substation, which is on Amplats property, was set alight.
"Since then we have been having running clashes with groups of about 1,000 people who formed a barricade to prevent police from entering," he said.
Amplats said it would give the workers a one-off "hardship allowance" of $230 (£140), as part of a deal struck with trade unions, including the National Union of Mineworkers (NUM), to end the strike.
But a protester, MacDonald Motsaathebe, told Reuters news agency that workers would not resume work until their wage demands are met.
"We earn peanuts," he is quoted as saying.
Analysts say workers across the industry are disaffected with the NUM and other mainstream unions, regarding them as too close to employers and government officials.
The workers have been demanding $1,840 in monthly pay, more than three times their current average salary.
Income levels between South Africa's workers and employers are among the most unequal in the world.
Earlier this month, President Jacob Zuma called on company bosses to take a salary freeze.
South Africa is one of the world's biggest producers of precious metals.