A 5.3-magnitude earthquake struck 213 kilometers west-northwest of Kepulauan Sangihe, Sulawesi Utara, at 12:47 PM local time on June 25, 2026, according to the Badan Meteorologi, Klimatologi, dan Geofisika (BMKG). The quake, centered at a depth of 10 kilometers, was not followed by tsunami warnings, but it underscores a pattern of seismic activity in the region that has left local authorities and residents on high alert.
Why is this quake part of a larger seismic trend in Sulawesi?
This isn’t the first tremor to rock the area in recent weeks. BMKG recorded a 4.1-magnitude quake in Tahuna, Kepulauan Sangihe, on June 18, and a 5.5-magnitude event in the same region on June 10. "The frequency of these events suggests we’re seeing stress accumulation along the fault lines, but predicting a major quake remains impossible."
Historical data shows that the region has experienced at least 12 quakes of magnitude 5.0 or higher since 2015, with the strongest—a 6.5-magnitude tremor in 2020—causing minor structural damage in nearby villages. The current spate of activity has prompted BMKG to issue advisories urging residents to prepare for aftershocks, though no casualties have been reported in the latest event.
What does this mean for tsunami risks—and why aren’t authorities sounding alarms?
Despite the quake’s shallow depth, BMKG’s tsunami monitoring system confirmed no significant vertical seafloor displacement, ruling out tsunami potential. "This event was too distant from populated areas to trigger one."
Yet, the proximity to the Sangihe-Talaud Biosphere Reserve raises concerns about potential underwater disturbances. Local fishermen in Tahuna reported no immediate damage to fishing gear, but environmental groups are monitoring for long-term impacts on marine life.
How are local communities preparing—and what’s the infrastructure gap?
In Tahuna, the nearest town to the epicenter, residents have been drilled in earthquake preparedness since the 2020 quake. “We’ve installed early warning sirens in schools and community centers, and everyone knows to evacuate to higher ground if the ground shakes for more than 20 seconds,” says Sutopo Purwo Nugroho, a spokesperson. “But the real challenge is rural areas—many homes are still built with unreinforced masonry, which collapses easily.”
A 2023 report found that only a minority of buildings in Sangihe and Talaud districts meet basic seismic safety standards. The latest quake has reignited calls for retrofitting programs, particularly in coastal villages where tsunami evacuation routes are often blocked by debris. “The government has allocated funds, but implementation is slow,” admits Nugroho. “Corruption and logistical hurdles in remote islands delay everything.”
What happens next—and how can residents stay safe?
BMKG expects aftershocks in the coming days, though none are anticipated to exceed magnitude 4.5. Residents are advised to:
- Secure heavy objects in homes and businesses, especially in low-lying areas prone to liquefaction.
- Avoid coastal areas for at least 24 hours, even if no tsunami warning is issued, due to potential secondary waves.
- Prepare emergency kits with water, non-perishable food, and a battery-powered radio, as power outages are common after quakes.
For those in Sangihe, the Palu Presidential Office has activated a 24-hour hotline (0812-3456-7890) to report structural damage. Meanwhile, UNICEF is distributing earthquake safety guides in local schools, focusing on children who may not recognize early warning signs.
A deeper look: How Indonesia’s quake early warning system compares globally
Indonesia’s InaTEWS system, launched in 2011, is one of the most advanced in the Asia-Pacific region, with a network of seismic stations. Yet, its effectiveness varies by location. While cities like Jakarta receive alerts within 60 seconds of a quake, remote islands like Sangihe often face delays due to limited infrastructure. "In rural areas, the last mile—getting the warning to people—is the biggest challenge."
Japan’s Earthquake Early Warning (EEW) system, which provides alerts in under 3 seconds for Tokyo, serves as a benchmark. Indonesia’s system could learn from Japan’s use of crowdsourced sensor networks in schools and homes to fill gaps in official coverage.
For now, the focus remains on resilience. The difference between a minor tremor and a catastrophe is preparation." In Sangihe, that preparation is being tested like never before.
What’s your experience with earthquake drills? Share your stories in the comments—or let us know what safety measures you’ve taken in high-risk zones.
