1,624 Aftershocks Recorded in NTT, Largest at Magnitude 6.2
The Meteorology, Climatology and Geophysics Agency (BMKG) has recorded 1,624 aftershocks in East Nusa Tenggara (NTT). The largest aftershock measured magnitude 6.2.
Director of Earthquakes and Tsunamis at BMKG, Wijayanto, said the data was compiled up to 11.00 WIB. Among the thousands of aftershocks, 23 measured magnitude 5 and 59 were felt by residents.
Wijayanto said BMKG has deployed a joint team to conduct a damaging earthquake survey. The survey aims to support post-disaster recovery and reconstruction efforts.
“BMKG has deployed a joint team from headquarters and regional technical units to conduct a damaging earthquake survey, including macroseismic surveys, microtremor and MASW measurements to determine soil characteristics and response to shaking, aftershock monitoring, and verification of tsunami impacts in the field,” Wijayanto explained in his statement on Monday (17/8/2026).
BMKG has also carried out public outreach and helped reassure residents in dealing with post-earthquake conditions. The public is urged to avoid buildings that are cracked or damaged by the earthquake and to remain alert for ongoing aftershocks.
The first earthquake occurred in the Flores region on Saturday, 15 August 2026 at 04.58 WIB with updated parameters of magnitude 7.7, triggering a tsunami in surrounding areas. This shallow earthquake was caused by tectonic activity in the Flores Back-Arc with a thrust fault mechanism.
Affected areas included North Manggarai, North Ngada, Ende, East Flores and Jeneponto with Siaga (alert) status, and East Flores, Bima, Dompu and Wajo with Waspada (advisory) status. The early tsunami warning was declared over at 07.30 WIB, 2 hours 31 minutes and 37 seconds after the earthquake.
Head of the National Disaster Management Agency (BNPB) Lieutenant General TNI Suharyanto previously confirmed that the death toll from the NTT earthquake had reached 54 as of today. Data collection on injuries is still ongoing.
He instructed local governments to carry out damage assessment in parallel and in stages without waiting for data to be 100 per cent complete, so that repair interventions can be executed immediately.
“Data collection on damaged residential houses, whether lightly, moderately or heavily damaged, is our top priority. Damage to public facilities such as the regent’s office is the next priority after residential needs are met,” Suharyanto said in his statement.
“Data collection does not need to wait for everything to be completed; as soon as valid data comes in, repairs will be processed immediately so that handling can proceed more quickly,” he added.