A powerful magnitude 7.7 earthquake gas struck off the coast of Indonesia, damaging buildings and homes, and triggering a tsunami warning

MAUMERE, Indonesia — A powerful magnitude 7.7 earthquake struck off the coast of Indonesia early Saturday, damaging buildings and homes, and triggering a tsunami warning. There were no immediate reports of casualties.

The U.S Geological Survey said the quake hit Indonesia’s Flores region with a depth of 10 kilometers at 5:58 a.m. Indonesia time. Its epicenter was 68 km (42 miles) north-northwest of the city of Ende in East Nusa Tenggara province.

The initial quake was followed by several aftershocks.

Indonesia’s Meteorology, Climatology and Geophysics Agency issued a tsunami warning for part of East Nusa Tenggara, West Nusa Tenggara, South Sulawesi and Southeast Sulawesi provinces, and urged residents to stay away from beaches and riverbanks. The agency located the shallow undersea quake near Flores island. Residents along affected coastlines were advised to move to higher ground as officials were closely monitoring coastal tide gauges for any changes.

The quake was felt across much of Flores Island. Initial reports indicated there was damage to homes and public facilities, though officials had not yet released estimates of the number of damaged buildings or any casualties.

Yohanna Embu, a resident of Sikka, a regency within East Nusa Tenggara province, said a number of buildings were damaged by the strong shaking and panicked people ran to higher ground.

“Many buildings here were damaged … I saw that the waiting room at the Pelni port terminal in Maumere had collapsed,” she said.

Indonesia, a vast archipelago of more than 17,000 islands, is prone to earthquakes and volcanic activity because of its location on the “Ring of Fire,” an arc of volcanoes and fault lines in the Pacific Basin.

In December of 1992, a magnitude 7 earthquake caused a tsunami that killed about 2,500 people on the southeastern island of Flores, part of a group of islands in the eastern half of Indonesia.