A powerful magnitude 7.8 earthquake struck off the coast of Sarangani province on Monday morning, prompting the Philippine Institute of Volcanology and Seismology (Phivolcs) to issue a tsunami warning for nine coastal provinces in Mindanao.

Phivolcs recorded the earthquake at 7:37 AM and initially logged it at magnitude 7.0 with a depth of 10 kilometers. In a second advisory, the agency upgraded the magnitude to 7.8, with a revised depth of 33 kilometers. The epicenter was located 32 kilometers south-southwest of Maasim, Sarangani.

Phivolcs attributed the earthquake to movement along the Cotabato Trench. 

The tsunami warning covers the provinces of Sarangani, Davao Occidental, Tawi-Tawi, Sulu, Basilan, Zamboanga del Sur, Zamboanga Sibugay, Sultan Kudarat, and South Cotabato. Phivolcs warned that tsunami waves exceeding one meter above normal tide levels are expected. The first tsunami waves were forecast to arrive between 7:37 a.m. and 9:37 a.m. and may continue for hours. 

The strongest shaking was recorded at Intensity VII in General Santos City. Intensity VI was felt in Palimbang and Senator Ninoy Aquino in Sultan Kudarat, while Intensity V shaking hit Davao City, Kidapawan City, and several municipalities in Cotabato, Sultan Kudarat, and Zamboanga del Norte. 

The tremors were felt across a wide area of Mindanao, extending as far as Butuan City, Cagayan de Oro City, Malaybalay City, and parts of the Zamboanga Peninsula. Residents in portions of Leyte and Southern Leyte also experienced weak but noticeable shaking. 

Buildings collapse, casualties reported

A three-story commercial building housing a Jollibee restaurant and a Love Radio station collapsed in General Santos City. Parts of SM City General Santos and a building at Notre Dame of Dadiangas University also sustained major damage.

At least three people were killed, while authorities were still gathering reports on additional casualties, structural damage, and disruptions to infrastructure and utilities in affected communities. Several deaths have been confirmed by the Office of Civil Defense, while response teams are still trying to verify more reports of casualties on the ground. 

Benjie Ancheta, police chief of Alabel town in Sarangani, told Reuters that the police building sustained some cracks after the quake, which struck during their flag-raising ceremony. He said some people fainted following the strong tremor. "This is the strongest earthquake we've experienced," Ancheta said. 

Classes, government work suspended

The magnitude 7.8 earthquake disrupted the opening day of classes across parts of Mindanao, forcing the suspension of classes and government work and causing damage to buildings and infrastructure in several areas across the southern Philippines. 

In Sarangani, province-wide classes and work in government offices were suspended until further notice. The suspension covered all levels in public and private schools and all government offices in the municipalities of Alabel, Maasim, Maitum, and Malungon. 

Marcos orders immediate government response

President Ferdinand R. Marcos Jr. ordered all relevant government agencies to mobilize immediately and respond to the disaster.

"A strong earthquake has struck off the coast of Sarangani this morning, and a tsunami warning is now in effect across several coastal provinces in Mindanao. I have directed all relevant government agencies to act immediately," Marcos said in a statement.

The President called on residents in affected coastal provinces to evacuate without delay. "To our kababayans in the affected provinces, please heed the tsunami warning. Move to higher ground now. Do not wait. Your life is more important than anything left behind," he said. 

Marcos also ordered the suspension of classes in all levels across affected areas in Mindanao until further notice, stressing that the safety of students must come first. 

The President directed the DSWD to pre-position relief supplies and ensure evacuation centers are ready and operational for residents who may be displaced. He also ordered the DPWH to stand by for damage assessment and the clearing of roads, bridges, and other critical routes needed for rescue and relief efforts. 

Under the directive of President Marcos and Defense Secretary Gilberto Teodoro, DND and OCD officials immediately headed to the affected areas to assess damage and conduct response operations. OCD Administrator Undersecretary Harold Cabreros scheduled an immediate flight to General Santos City to personally oversee the deployment of relief goods and personnel. 

Marcos assured the nation that "the national government is moving and we will not leave Mindanao behind." 

Government response activated

The Department of Budget and Management assured the availability of quick response funds for concerned agencies to support disaster response efforts in Mindanao. "For the Sarangani earthquake response, existing QRF resources remain available for immediate deployment by the concerned agencies," the DBM said. 

The Department of Energy, through its Task Force on Energy Resiliency, activated coordination with electric cooperatives, distribution utilities, and oil industry stakeholders to assess the impact of the earthquake on energy facilities in Sarangani and nearby areas. 

The Civil Aviation Authority of the Philippines suspended operations at the General Santos Airport while assessment of facilities and equipment was underway. The Department of Health also activated all crisis protocols in all DOH hospitals and Center for Health Development offices in Mindanao. 

The Pacific Tsunami Warning Center said the tsunami threat had largely passed about five hours after the quake struck, but urged people to stay alert and heed warnings from local authorities, as sea levels may continue to fluctuate. 

Meanwhile, Phivolcs has lifted the tsunami warning for all coastal communities in the affected provinces of Mindanao. 

Authorities across the region, including in Indonesia, also cancelled their tsunami warnings, though a tsunami advisory remained in place for Japan's southern coast and outlying islands. 

The Pacific Tsunami Warning Center, which initially warned of possible waves of up to three meters, later said the tsunami threat had largely passed about five hours after the earthquake. 

Phivolcs reminded the public to remain vigilant for aftershocks and to continue following the instructions of local disaster risk reduction and management offices.

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