The Philippine Institute of Volcanology and Seismology (DOST-PHIVOLCS) issued a tsunami warning on 8 June, as wave heights were projected to exceed one meter in some coastal areas, particularly in enclosed bays and straits.

This follows a sea level monitoring, which confirmed that a tsunami did occur in multiple locations, with varying wave heights recorded such as Kiamba, Sarangani (1.48 meters), Kalamansig, Sultan Kudarat (0.84 meters), Maasim, Sarangani (0.48 meters), Zamboanga City (0.25 meters), Mati City, Davao Oriental (0.21 meters), and Tandag City, Surigao del Sur (0.09 meters).

Authorities reminded the public that while the tsunami heights were moderate in most areas, localized coastal flooding and strong currents are still possible, especially in low-lying areas.

Meanwhile, as of 11 June, monitoring data recorded a total of 2,968 seismic events related to the main earthquake. Of these, 777 were plotted, and 58 were reportedly felt by residents.

Aftershocks ranged in magnitude from 1.2 to 6.4, indicating continued seismic instability in the region.

Authorities stressed that aftershocks are expected to continue for days or even weeks following a major earthquake of this scale.

Residents in the affected region are advised to remain alert, follow official advisories, and avoid returning to coastal zones until authorities declare them safe.