Indonesia issues tsunami warning after powerful 7.7 magnitude earthquake

Indonesia issues tsunami warning after powerful 7.7 magnitude earthquake

A powerful earthquake struck off the coast of eastern Indonesia on Saturday, August 15, 2026, triggering early tsunami warnings across several regions of the archipelago. The tremor, which hit the Flores region, prompted officials to urge residents to move to higher ground and avoid riverbanks and beaches.

Data on the quake's strength and depth varied among monitoring agencies. The U.S. Geological Survey (USGS) and the European-Mediterranean Seismological Centre (EMSC) both recorded the magnitude at 7.7, while Geoscience Australia reported a magnitude of 7.8. The USGS estimated the quake hit at 5:58 a.m. Local time at a depth of 10 kilometres, though the EMSC placed the depth at 35 kilometres.

The epicentre was located 68 kilometres north-northwest of the city of Ende in East Nusa Tenggara province. Other reports placed the tremor off the northern coast of Sikka.

Indonesia's Meteorology, Climatology and Geophysics Agency (BMKG) issued tsunami warnings for Southeast Sulawesi, South Sulawesi, West Nusa Tenggara, and East Nusa Tenggara. While the agency monitored coastal tide gauges for changes, reports emerged of tsunami waves measuring less than 1 metre (3 feet) in several areas.

The main shock was followed by several aftershocks. The USGS recorded three strong tremors measuring 6.1, 5.9, and 5.6. BMKG also confirmed that multiple aftershocks occurred following the initial quake, which it recorded at 4:58 a.m. Local time at a depth of 15 kilometres.

The impact was felt strongly for approximately one minute in regions including Bima and Nagekeo, according to Dodi Yuleova, a spokesperson for the national disaster mitigation agency. While there were no immediate official reports of casualties, the USGS PAGER system estimated that 500,000 people were exposed to severe or very strong shaking.

Visual evidence of damage surfaced on social media and through news footage. A video verified by Reuters showed a building collapsing into rubble at a port in Maumere, the main town in Sikka Regency on Flores Island, as people ran through the streets. Kompas TV footage showed a hospital in the Ende district of East Nusa Tenggara province moving patients outside. Additionally, reports on social media suggested a hotel in Ruteng suffered damage.

Australia's tsunami warning centre monitored the situation but stated the undersea earthquake would have no tsunami threat to the Australian mainland, islands or territories.

Indonesia is located on the "Ring of Fire," an arc of fault lines and volcanoes in the Pacific Basin that makes the archipelago of more than 17,000 islands prone to volcanic activity and seismic events. The region has a history of catastrophic events, including a 9.1-magnitude earthquake off Sumatra in 2004 that caused a tsunami killing more than 220,000 people, with more than half of those deaths occurring in Indonesia.

Other recent significant events include a 7.5-magnitude earthquake and tsunami in Sulawesi in 2018, a 6.9-magnitude quake in Lombok in 2018, and a 6.5-magnitude tremor in West Java's Cianjur region in November 2022, all of which resulted in hundreds of deaths.