SANTIAGO, Chile — Northern Chile was shaken by a magnitude-8.2 earthquake Tuesday night that killed five people and forced the evacuation of coastal areas, prompting President Michelle Bachelet to order military leaders to the region to maintain order.

The quake struck at 9 p.m. local time 95 kilometers (59 miles) off the coast from the city of Iquique at a depth of 20 kilometers (12.4 miles), according to the U.S. Geological Survey. Four men and one woman were killed by heart attacks or falling debris, Interior Minister Rodrigo Penailillo said on national television.

"The country has been able to withstand these first few hours of emergency," Bachelet said on state television. "We've taken the necessary measures."

Hundreds of thousands of people were evacuated from the coast along the length of the country, causing traffic jams on the routes to higher ground. Copper prices rose to a three-week high on concern the quake would disrupt output in the world's biggest producer of the metal.

"At the beginning it was chaotic as people started evacuating in cars, which is not allowed," said Justin Sturrock, a resident in the northern city of Antofagasta. "The highway is blocked and there are traffic jams everywhere."

A tsunami warning was followed by waves as high as 2 meters (7 feet), emergency services reported. The government expects to maintain the evacuation order until at least 5:30 a.m., Penailillo said, while lifting the tsunami alert in the far south of the country.

Bachelet declared Arica-Parinacota and Tarapaca "catastrophe areas" and said she would travel to the region on Wednesday. Bachelet, who came in for criticism for not using the military quickly enough after a devastating earthquake near the end of her first term in office in February 2010, also said she would send the heads of various branches of the armed forces to the region to lead efforts to maintain order. The 2010 quake killed about 500 people and caused $30 billion in damage and losses.

While last night's quake caused some landslides and triggered at least one fire in Iquique, water and electricity supplies continued as normal in many areas, Television Nacional reported. Electricity has now been restored everywhere but the port city of Iquique, power distributor Cia. General de Electricidad said in emailed statements. A church tower in the town of Huara collapsed after the tremor, the local mayor Carlos Silva told TVN.

The government sent extra police to Iquique to help maintain order, Penailillo said. More than 300 convicts had escaped a prison in the city, he said.

There was an attempt at looting in the port of Iquique, regional governor Gonzalo Prieto told Radio Cooperativa. Air force troops were bolstering police who were guarding supermarkets and gas stations in the region, he said.

Copper climbed for a second day with the contract for delivery in three months on the London Metal Exchange added as much as 1 percent to $6,728.75 a metric ton, the highest intraday level since March 10, and was at $6,675.25 at 10:20 a.m. in Tokyo. Wednesday's gain pares the metal's loss this year to 9.3 percent.

Teck Resources' Quebrada Blanca mine in northern Chile was operating normally after the earthquake, spokeswoman Claudia Onetto said in an emailed response to questions. Quebrada Blanca is located adjacent to Anglo American and Glencore Xstrata's Collahuasi mine near the border with Bolivia.

Collahuasi was undamaged by the tremor, labor union official Cristian Arancibia told Radio Cooperativa. Workers at the mine were evacuated after the quake, he said.

Codelco, the world's largest copper producer, said its mines located in the Antofagasta region further south were unaffected by the earthquake, a company spokesman briefed on the matter said. The company evacuated workers from its Ventanas refinery division and from Mejillones where Codelco is building a molybdenum plant. Three ships that were waiting to load at the Angamos port in Mejillones put further out to sea, the spokesman said.

Empresa Nacional del Petroleo's Bio-Bio refinery was not affected by the evacuation, said a company official briefed on the matter.

Iquique has seen a series of tremors over the past few weeks and a larger earthquake was not a surprise, Bruce Tresgrave, a geophysicist with the USGS, said on Bloomberg TV.

"Chile is actually quite well prepared for tsunamis," he said. "There is always the possibility of communications failure."