On 15 August 2026, a powerful magnitude 7.8 earthquake struck off the northern coast of Flores, Indonesia, caused by movement on the Flores back-arc thrust fault. The quake, which reached a maximum intensity of VIII (Severe), triggered a 1.61-meter tsunami and resulted in at least 129 deaths, 1,723 injuries, and damage to nearly 98,900 homes, with over 27,400 collapsing or severely damaged. Occurring within the seismically active Pacific Ring of Fire, the event resulted from the convergence of the Sunda and Australian plates, where the back-arc thrust accommodates about 10 mm of movement per year. This specific fault segment had been previously identified as capable of generating a magnitude 7.8–7.9 quake, and the region has a history of destructive events, including the 1992 Flores earthquake and other tsunamigenic quakes. Following the main shock, the BMKG recorded 9,765 aftershocks, including 134 exceeding magnitude 4.0, highlighting the ongoing seismic activity. The earthquake underscores the substantial tsunami and seismic risk associated with the lesser-studied eastern part of Indonesia's back-arc thrust system.