At least 47 people have been killed in an earthquake off the coast of Indonesia in the eastern Flores region.

The United States Geological Survey reported that the magnitude 7.7 earthquake struck early Saturday morning and centered in waters north of the island, about 1,000 miles east of the capital, Jakarta.

The epicentre was 42 miles north-northwest of Ende, a city in East Nusa Tenggara province. Although the epicentre was offshore, the earthquake damaged nearby communities on Flores Island, part of the province.

A dozen strong aftershocks followed the disaster and worsened impacts on residents.

Indonesia, an archipelago of some 17,500 islands, is prone to earthquakes and volcanoes. It sits on the Pacific “Ring of Fire” and is a hot spot for tectonic activity due to the convergence of the Australian and Sunda tectonic plates.