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SANTIAGO - Two people are confirmed dead with at least 50 others trapped in a tunnel, after a magnitude 7.7 earthquake struck mineral-rich northern Chile overnight.
More than 100 people have been injured, cars crushed and buildings destroyed, as massive dust clouds rose into Chile's mountainous northern sky.
"At the Galleguillos tunnel we understand there are some 50 people trapped," Navy Captain Ignacio Rojas told local television. "However, we are receiving information now that there could be more people trapped inside."
Hundreds of miles away in the Chilean capital Santiago, buildings swayed and unnerved even the earthquake-hardened.
The worst damage occurred in Tocopilla, 120 kilometres north of coastal mining city Antofagasta, where people were caught under rubble from crumbling rooftops and balconies.
Authorities said an 88-year-old woman was killed when a wall fell on top of her in Tocopilla. A 54-year-old woman also died in the small city, although the cause of death was not immediately clear.
Aid group World Vision International, which sits on a disaster relief committee for the Chilean government, said it had information suggesting the situation in Tocopilla could be far worse than reported so far.
Television images showed cars crushed under the concrete awning of a hotel in Antofagasta, where the quake knocked out power and phone services.
"People ran out into the streets because of how prolonged the quake was. There was a lot of alarm but no material or human damage," police chief Hernan Tamayo said in Arequipa, a town farther north near the Peruvian border.
The United States Geological Service, or USGS, said the quake, 60km deep, was centred 106km west of the town of Calama and struck at 12:40pm local time (NZT4.40AM).
The quake was initially reported at 7.8 magnitude by the US agency and later verified at 7.7. Just two hours later, a second quake of 5.7 magnitude struck in the same northern region.
The quakes hit an area of many large copper mines. Chile is the world's biggest copper producer, providing more than a third of annual supplies of the red metal.
BHP Billiton said work was paralysed after power was cut off at its Escondida, Spence and Cerro Colorado copper mines.
Freeport-McMoRan Copper & Gold said it later resumed operations at its Candelaria mine in Chile, but its El Abra mine was still down without power.
Chilean state copper miner Codelco said it resumed operations at its largest division, Codelco Norte, two hours after the quake left it temporarily without power.
Big mines in the south of Peru, also a major global metals producer, said operations were not impacted.
The earthquake did not trigger a tsunami along Chile's Pacific coast and initial warnings were lifted.
The earthquake was felt in Peru and Bolivia, Chile's neighbours to the north, and in Santiago, 1,400km south of the epicentre.
Chile, like other countries around the Pacific Rim's "ring of fire" earthquake zone, has a long history of strong quakes, including the strongest recorded in recent history - the 1960 9.5 magnitude Valdivia quake that killed thousands of people.
- REUTERS
