Tsunami warnings have been issued across four provinces in central and southern Indonesia after a powerful magnitude-7.7 earthquake struck off the coast of Flores island early on August 15, damaging local infrastructure and leaving at least two people dead, Kompas reports.

The shallow tremor occurred at 04:58 local time at a depth of 15km, with its epicenter located roughly 30km north-east of Mbay in East Nusa Tenggara (NTT) province, according to bulletins released by Indonesia’s Agency for Meteorology, Climatology, and Geophysics (BMKG).

Modelling by the agency triggered immediate evacuation orders across coastal areas vulnerable to sea-level surges. Authorities in NTT, West Nusa Tenggara (NTB), South Sulawesi, and Southeast Sulawesi have instructed local emergency bodies to move residents inland.

Under BMKG protocols, districts placed under high-level Siaga (Alert) status were ordered to clear coastal settlements entirely, while those under Waspada (Advisory) status warned residents away from shorelines and river estuaries. Initial sea-level gauges recorded minor tsunami waves reaching 0.36 metres at Labuan Bajo and 0.19 metres at Sikka.

Disaster response agency BPBD confirmed two deaths in the Sikka regency. The quake also caused structural damage to Frans Sales Lega Airport in Ruteng and damaged several hotels in the tourism hub of Labuan Bajo, raising concerns over transport bottlenecks as relief operations get under way.

At least 26 aftershocks have been registered along the Flores back-arc thrust line. Regional officials said efforts are focused on restoring operations at damaged airfields and harbours to allow medical supplies and emergency logistics to reach remote districts, while engineers inspect commercial and residential structures for safety.