All day Wednesday the ground was still shaking with aftershocks, leaving thousands afraid to go back inside their homes. A magnitude-7.8 aftershock struck about 25 miles off the coast of Chile near Iquique Wednesday night.
Chile's President Michelle Bachelet declared a state of emergency in the region. Some of the six who died were crushed to death, while others had heart attacks.
It's possible that other people were killed in older structures made of adobe in remote communities that weren't immediately accessible, but it's still a very low toll for such a powerful shift in the undersea fault that runs along South America's Pacific coast.
Tuesday's quake struck 59 miles northwest of Iquique, Chile, at 8:46 p.m. local time, according to U.S. Geological Survey. The shaking caused landslides that blocked roads, power failed for thousands, an airport was damaged and several businesses caught fire. About 300 inmates escaped from a women's prison in the city of Iquique.
Residents along the coast were moved to higher ground because of tsunami fears, but most have begun to return home as tsunami warnings were lifted. Riot police joined about 300 soldiers in the area to prevent looting and to round up escaped prisoners.
About 2,500 homes were damaged in Alto Hospicio, a poor neighborhood in the hills above Iquique.
More than 20 significant aftershocks followed, including one of magnitude 6.2.
The region is one of the most seismically active areas in the world because just off the coast, the Nazca tectonic plate plunges beneath the South American plate, pushing the towering Andes cordillera to ever-higher altitudes. Four years ago, an 8.8-magnitude earthquake hit the area, setting off a powerful tsunami. Bachelet's emergency preparedness office had prematurely waved off a tsunami danger.
Most of the 500 dead from that tremor survived the shaking, only to be caught in killer waves that destroyed 220,000 homes and washed away large parts of many coastal communities.
The Associated Press contributed to this report.