A powerful magnitude 7.7 earthquake struck off the coast of Indonesia’s Flores Island on Saturday morning, killing at least 47 people and injuring 50 others, according to the country’s disaster mitigation agency, BNPB.

The earthquake struck around 6 a.m. local time, about 68 kilometres northwest of Ende in East Nusa Tenggara province. The strong shaking damaged health care facilities, schools, government offices, and more than 50 homes.

About 2,000 residents were evacuated from Nagekeo Regency as a precaution. Authorities initially issued a tsunami warning, but later lifted it. Waves reaching up to one metre were recorded in Maurole, Ende.

The earthquake also caused landslides and made some roads difficult to access. Emergency teams, including rescue workers and a helicopter, were deployed to assist affected communities and search through damaged areas.

At a seminary in Sikka, students were attending morning Mass when part of an assembly hall collapsed. The incident caused people to flee in panic, while at least one priest suffered a broken leg.

The earthquake was felt across Flores, a mountainous island with a population of about two million. Indonesia is highly prone to earthquakes because it sits along the Pacific Ring of Fire.

Hours later, another magnitude 6.9 earthquake struck northern Sumatra, according to the US Geological Survey.