At 8:46 p.m. the rumbles began in Iquique Province. For 40 seconds in this north Chilean region that’s cradled civilization since 7000 B.C., an 8.2 magnitude earthquake shook both earth and ocean. For those 40 seconds, people scrambled for door frames, clutched countertops and loved ones. Then, when the violence of the moment subsided, there was but one horrifying thought. Worse may still be on the way.

All across Iquique, a somnolent city that rests 60 miles from quake’s epicenter, sirens wailed in the darkness. At an office building, a man in a red polo looked upon a floor strewn with spilled documents. Inside a darkened hovel, a man screamed for the others to shut up, be careful, and get outside now. Thousands of Chileans likewise streamed into the streets. But would it be safer there?

A tsunami may be coming, the news told them. The earthquake had been a result of “thrust faulting at shallow depths near the Chilean coast, reported the United States Geological Survey. Authorities were hollering at people to evacuate before the possible tidal wave arrived.

North and South along the Pacific coast in Peru and Chile, a country pummeled by some of the largest earthquakes on record, towns were looking to do the same. There were whispers of the Fukushima quake-tsunami combination that claimed nearly 16,000 lives three years ago and destroyed or damaged hundreds of thousands of buildings, not to mention the 2004 Sumatra tsunami that killed 230,000.

Soon, two incendios fires erupted inside Iquique buildings, and rumors spread of looters targeting stores. Then came even scarier news: The quake had crushed to death or induced fatal heart attacks in at least six people. Power outages had plunged some of the city into blackness. Landslides had stranded people on a mountainside road. Three hundred inmates at a women’s prison had been freed. Coastal hospitals were being evacuated.

Some of Iquique’s 180,000 residents fled for a local stadium and unfurled blankets. Others massed before the stately Hospital del Salvador, unsure of what to do next. Many more took to Twitter, as a wave of social media emblazoned with the hashtag #prayforchile washed across the Internet.

Tense minutes gave way to tense hours. Everyone seemed to be either be on a phone checking for news or calling for loved ones.

But then the night’s panic subsided. The government announced it had dispatched at least 300 members of the “armed forces to lend a sense of order to the city; Chilean police said they’d captured 16 of the escaped prisoners, and more prison guards were on the way.

Finally at 2 a.m., nearly four hours after the earthquake struck, the Pacific Tsunami Warning Center canceled its tsunami warnings for Chile and Peru.

Relief settled across Chile. At a time when horrific natural disasters have become an everyday part of the news cycle, it appeared one finally missed. “Luckily, so far, prominent Chilean journalist Andres Azocar tweeted. “It seems not to have been a disaster.

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