Chile's Codelco suspended copper production for an entire day at one of its four mining divisions July 10 and cut back operations at another plant following violent protests by striking workers, in the most serious flare-up yet in a two-week stand-off between management and subcontracted workers who are demanding improved pay and conditions.

Codelco—the world's biggest copper miner, providing more than 10% of world demand—stopped extraction at its El Teniente division in central Chile after protesters wrecked trucks carrying copper from the mine and hurled stones at buses transporting workers to their shifts. El Teniente, 100 kilometers south of Santiago, is the second-largest of Codelco's four mining divisions and home to the world's biggest underground copper mine.

The striking workers are not employed directly by the parastatal Codelco but are subcontracted for such tasks as earth clearing, catering, truck driving and cleaning at the company's mines. They are demanding that their salaries be brought more into line with the company's unionized staff.

The strike at Codelco comes as workers have walked out at one of Chile's largest privately owned copper mines, Collahuasi, in the extreme north of the country. Collahuasi, majority-owned by industry heavyweights Xstrata Plc and Anglo American, produces around 8 percent of Chile's copper. The Collahuasi strike prompted a spike in the price of copper in international markets July 9. (Reuters, July 10)

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