Chile - Chile's government sent more troops to restore order and hand out aid in the country's second-largest city on Tuesday after a devastating earthquake unleashed a wave of looting.

A curfew in the badly damaged city of Concepcion was extended until midday, a day after hordes of desperate residents smashed into shuttered stores, carting off whatever they could find, and set fire to at least one supermarket.

Some people armed with sticks and shotguns banded together with neighbors to protect their stricken homes and many complained that government food aid and other supplies were arriving too slowly.

Thousands of troops were deployed to reinforce local police and President Michelle Bachelet said on Tuesday that order had been restored in the city, which bore the brunt of Saturday morning's 8.8-magnitude quake that killed at least 723 people.

Bachelet warned that looting would not be tolerated, dispatched 11,000 soldiers and imposed curfews to restore order in the worst-affected central region, where more strong aftershocks rattled nerves on Tuesday.

We're going to get everywhere with the aid people need, Bachelet said before meeting U.S. Secretary of State Hillary Clinton, who arrived in Santiago with communications equipment to help the aid operations.

Food, blankets and medical equipment was being sent to some of the estimated 2 million people affected by the quake, but residents complained of skyrocketing prices of everyday staples like bread and milk.

Most of Concepcion remained without water and electricity as rescue teams worked with shovels and drills to find possible survivors in the rubble of a collapsed 14-storey apartment block.

ECONOMIC DAMAGE

Chile has the most stable economy in Latin America but the huge quake and tsunamis have hit its efforts to recover from a recession brought on by the global financial crisis.

It also lands billionaire businessman Sebastian Pinera with a mammoth reconstruction challenge days before he is sworn in as Chile's new president. The total economic damage from the quake could exceed $15 billion, the catastrophe risk firm AIR Worldwide said.

But both the human and economic cost could have been a lot worse given the size of the quake, one of the world's biggest in the past century.

The government acknowledges it has struggled to provide aid swiftly because of crumpled highways and major power disruptions caused by the quake.

Residents criticized the aid response in the battered central city of Talca, where the main hospital partly collapsed, forcing doctors and nurses to treat wounded quake victims in a clinic.

We haven't got any help from the government. We were expecting more and are still waiting for the three basics -- food, water and electricity, Damian Vera Vergara, 68, said.

MASSIVE WAVES

Saturday's quake sent massive waves surging into villages on the country's Pacific coast.

In the town of Constitucion alone, 350 people were believed to have died, and the full scale of damage in isolated coastal towns remained unclear.

We stayed in the house during the quake and then my wife started worrying about the sea coming in ... so we scrambled inland, said Manuel Parra, 64, whose simple seafront home was washed off its foundations.

Those who went inland up the hill survived. Those who didn't are no longer here.

Chile is the world's leading copper producer and supply concerns at first pushed global copper prices sharply higher but the country's main mines have resumed work and prices fell sharply on Tuesday.

The Chilean peso opened higher on bets the government and pension funds will repatriate offshore funds to pay for the reconstruction effort.

The central bank has said it would keep interest rates at record lows to help stimulate the economy.

(Additional reporting by Terry Wade in Constitucion and Simon Gardner and Alonso Soto in Santiago; Writing by Stuart Grudgings and Helen Popper; Editing by Kieran Murray)

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