(VIDEO) 10 Things to Know About the Devastating Back-to-Back Earthquakes That Hit Venezuela

Venezuela's northern coast was hit by two powerful earthquakes within a minute of each other on Wednesday, collapsing buildings and sending residents fleeing onto the street. Here are 10 things to know about the disaster as rescue efforts continue.

1. Two Massive Quakes Struck Less Than a Minute Apart

A magnitude 7.2 foreshock took place near San Felipe, the capital city of Yaracuy state, just after 6:04 p.m. ET. Just 40 seconds later, it was followed by a larger 7.5-magnitude earthquake, some 23 kilometers southeast of Yumare, also in Yaracuy state. The epicenters, which USGS estimated to be about 3 miles apart, were near the town of Morón on Venezuela's Caribbean coast, some 100 miles west of Caracas.

2. The USGS Warned of Mass Casualties

"High casualties and extensive damage are probable, and the disaster is likely widespread," the USGS said, initially estimating the death toll would most likely range from 10,000 to 100,000. On Wednesday evening, USGS modeling of the 7.5-magnitude earthquake estimated deaths could be in the thousands to tens of thousands, with economic losses reaching billions to tens of billions of dollars, said Paul Earle, a seismologist at USGS.

3. It's the Largest Quake to Hit Venezuela in Over a Century

The strongest of the "doublet," as the USGS described the twin quakes, is the largest earthquake to strike Venezuela since 1900, when a 7.7-magnitude quake hit the country, according to USGS.

4. A State of Emergency Has Been Declared

Acting Venezuelan President Delcy Rodríguez confirmed there have been fatalities in a national address, but did not give any numbers. Rodríguez declared a state of emergency, said several Venezuelan states had sustained damage, and called for unity, urging "our population to remain calm."

5. Caracas's Main Airport Has Closed

Damage was reported at Caracas' Simón Bolívar International Airport, where flights are now suspended. Rodríguez announced in remarks on state television that the airport in Caracas is closed due to heavy damage.

6. Buildings Collapsed Across Multiple Caracas Neighborhoods

Interior Minister Diosdado Cabello said the quake could be felt in several states, adding that the Altamira neighborhood in Caracas had "alarming situations" with collapsed homes and buildings. In Chacao, an eastern Caracas municipality, Mayor Gustavo Duque told broadcaster Globovision that two structures had collapsed, 16 people were injured, and that there were deaths too, though he gave no figure for fatalities.

7. The Tsunami Threat Has Been Lifted

A tsunami advisory was issued immediately after the quakes for much of the Caribbean, including Puerto Rico and the Virgin Islands. The National Weather Service U.S. Tsunami Warning System has since confirmed that the advisory has been lifted: "There is no longer a tsunami threat from this earthquake."

8. Residents Described Unprecedented Terror

Manuel Guevara Baro, who lived through a 1967 earthquake that killed more than 200 people in Caracas, told CNN this week's quakes were unlike anything he'd previously experienced. "I lived through the earthquake in Caracas in 1967, which was an earthquake that also had many victims, but was nothing like this earthquake we lived today," Guevara Baro said. "I could not even walk because of the intensity of the movement." Eighty-year-old Caracas resident Maria Romero echoed that comparison: "This earthquake was horrible, even worse than the one in 1967."

9. Significant Aftershocks Are Expected to Continue

Rodríguez noted that there had been 20 aftershocks recorded in the hours following the initial quakes. According to USGS forecasting, there's a 40% chance that, in the next week, a magnitude 6 or larger earthquake will strike in the same region, Earle said, and an "almost certainty" of an earthquake measuring at least magnitude 5.

10. The Region Has a Long History of Devastating Earthquakes

Venezuela sits along a complex and active tectonic boundary where the Caribbean Plate interacts with the South American Plate, creating a zone of frequent earthquakes across the country's northern region. Historically, the region has experienced several damaging events, including the devastating 1812 Caracas earthquake, estimated at magnitude 7.5 or higher, which killed thousands, and more recent events such as the 2018 magnitude 7.3 quake along the country's northern coast.

A Crisis Compounding an Already Strained Population

Beyond the immediate physical destruction, the earthquake's impact has been deepened by Venezuela's broader humanitarian and economic crisis. The lack of cellphone signal in parts of Venezuela deepened the distress of many families, particularly those among the more than 7.7 million people who have left the country during its protracted crisis, complicating efforts by those abroad to reach loved ones in the aftermath.

Effects Felt Across the Region

The earthquakes' impact extended well beyond Venezuela's own borders. Buildings in Manaus, Belém, and Macapá in Brazil's Amazon region were evacuated, according to reports on TV Globo, while the U.S. embassy in Caracas said it was closely monitoring the aftermath of the quake and urged American citizens in the country to seek secure shelter and avoid damaged areas.

An Outpouring of Support From Abroad

Exiled Venezuelan opposition leader María Corina Machado wrote on social media, "My heart, my infinite embrace, and my prayers are with every Venezuelan home in these hours of anguish. May strength, serenity, and solidarity prevail among us in the face of this difficult moment."

With hundreds of emergency workers continuing search-and-rescue operations through the night and the USGS warning of a continued likelihood of significant aftershocks in the days ahead, Venezuelan authorities face an enormous and rapidly evolving humanitarian response. Given the preliminary USGS death toll estimates ranging into the tens of thousands and widespread damage already confirmed to housing, infrastructure, and the country's main international airport, the full scope of the disaster is expected to become considerably clearer in the coming days as rescue and recovery efforts continue across the affected region of northern Venezuela.