Gold miners form a human chain while digging an open pit at the Chudja mine in the Kilomoto concession near the village of Kobu, 100 km (62 miles) from Bunia in north-eastern Congo, February 2009. Civil conflict in Congo has been driven for more than a decade by the violent struggle for control over the country's vast natural resources, including gold, diamonds and timber, most of which is exploited using hard manual labour.

Gold miners form a human chain while digging an open pit at the Chudja mine in the Kilomoto concession near the village of Kobu, 100 km (62 miles) from Bunia in north-eastern Congo, February 2009.

A gold miner scoops mud while digging an open pit at the Chudja mine in the Kilomoto concession near the village of Kobu, 100 km (62 miles) from Bunia in north-eastern Congo, February 2009.

Gold miners form a human chain while digging an open pit at the Chudja mine in the Kilomoto concession near the village of Kobu, 100 km (62 miles) from Bunia in north-eastern Congo, February 2009. Home to the world's biggest reserves of cobalt -- used in batteries, ceramics and dyes -- Congo has gold, silver and diamond mines, and holds some of the world's largest stores of copper, tin and metals such as tungsten, a component of many mobile phones.

Gold miners form a human chain, passing pans of mud up a slope, then throwing the empty pans down again, while digging an open pit at the Chudja mine in the Kilomoto concession near the village of Kobu, 100 km (62 miles) from Bunia in northeastern Congo, February 2009. Civil conflict in Congo has been driven for more than a decade by the violent struggle for control over the country's vast natural resources, including gold, diamonds and timber, most of which is exploited using hard manual labour.

A gold miner catches an empty pan thrown down a human chain while digging a pit at the Chudja mine in the Kilomoto concession near the village of Kobu, 100 km (62 miles) from Bunia in north-eastern Congo, February 2009.

Gold miners form a human chain, passing pans of mud up a slope, then throwing the empty pans down again, while digging an open pit at the Chudja mine in the Kilomoto concession near the village of Kobu, 100 km (62 miles) from Bunia in north-eastern Congo, February 2009.

A gold miner pauses for a smoke while digging a pit at the Chudja mine in the Kilomoto concession near the village of Kobu, 100 km (62 miles) from Bunia in northeastern Congo, February 2009.

A gold miner inspects a rock while digging a pit at the Chudja mine in the Kilomoto concession near the village of Kobu, 100 km (62 miles) from Bunia in northeastern Congo, February 2009.