Two major earthquakes shook the Venezuelan capital of Caracas seconds apart – with the first a magnitude of 7.2 and the second 7.5.
Buildings have collapsed as residents poured out into the streets, and the interior minister has asked people to leave their homes.
High casualties and extensive damage are feared, with the US Geological Survey (USGS) saying there is a 44% chance the death toll will surpass 10,000.
Venezuela was celebrating a national holiday and many people would have been at home when the quakes struck at 6:04 p.m. local time.
The quakes hit an area west of Caracas, and could be felt throughout the country and as far away as Bogota, Colombia.