NORTH SUMATRA / RankWire.AI / – On Tuesday, a magnitude 6.1 earthquake was registered off the coast of North Sumatra in Indonesia, causing tremors across several regions in Sumatra. The seismic event took place at 1:02:23 p.m. western Indonesian time, which corresponds to 06:02:23 UTC. According to official measurements, the epicenter was located in the sea, approximately 147 kilometers southeast of South Nias Regency. The quake originated at a depth of 29 kilometers beneath waters west of Sumatra.

The BMKG, Indonesia’s Meteorology, Climatology and Geophysics Agency, identified the earthquake’s coordinates at 0.65 degrees south latitude and 98.32 degrees east longitude. The strongest recorded shaking was in North Tapanuli, with residents experiencing a level IV intensity. Several parts of West Sumatra also experienced noticeable tremors, including communities in Padang, Padang Pariaman, Pariaman, West Pasaman, and Agam.
Reports of shaking from other areas in Sumatra were also received following the magnitude 6.1 quake. The National Disaster Mitigation Agency, known as BNPB, confirmed that this seismic event posed no risk of generating a tsunami. In South Nias, residents felt weak tremors lasting approximately three to five seconds. Emergency response teams in local disaster offices began monitoring the affected zones, and the initial national bulletin did not report any casualties or damage figures at that time.
No tsunami threat announced by officials
The intensity of shaking was recorded as III to IV in Padang, Padang Pariaman, Pariaman, West Pasaman, and Agam. Padang Sidempuan, Subulussalam, and South Nias experienced intensity III, while Padang Panjang and Central Tapanuli recorded levels of II to III. Gunungsitoli registered intensity II. These data indicated that residents across multiple provinces felt the earthquake, although the reported levels of shaking differed depending on the location.
Authorities advised the public to stay calm and rely solely on official earthquake updates in light of the offshore seismic activity. Residents were urged to inspect their homes and structures for cracks or possible damage. If a stronger earthquake occurs, they should move to open spaces. Additionally, officials recommended that individuals near the coast avoid beaches following strong aftershocks as part of the safety measures issued after the incident.
Continued surveillance after offshore seismic event
Official earthquake data on Wednesday confirmed the event near South Nias remained at magnitude 6.1 with a depth of 29 kilometers. The epicenter was still listed as 147 kilometers southeast of South Nias. No tsunami warning had been issued based on the most recent official updates. Local disaster response teams continued their post-quake assessments to evaluate potential impacts on communities affected by the tremor.
The seismic event occurred on August 18, during which residents across western Indonesia received alerts and reports concerning the offshore earthquake. Authorities persisted in guiding the public toward verified information and safety protocols. People in vulnerable areas were advised to avoid buildings showing damage and to remain vigilant for further aftershocks. Confirmed reports maintained that the quake was a magnitude 6.1 offshore event with no tsunami threat.
