Rescue operations continued in General Santos City, one of the areas hardest hit by Monday’s earthquake, after a strong aftershock forced emergency personnel to evacuate a partially collapsed three-story grocery building where search teams were looking for a missing employee.

Approximately 30 firefighters and coast guard personnel scrambled to safety when fresh tremors shook the damaged structure, sending concrete debris crashing from the building. Rescue operations were temporarily halted while authorities reassessed safety conditions at the site.

The earthquake, among the strongest to strike the Philippines in decades, caused widespread destruction across southern Mindanao, the country’s second-most populous region. Officials said more than 25,000 people remained displaced, many housed in 45 government-run evacuation centers as persistent aftershocks heightened fears of additional building collapses.

Teresito Bacolcol, director of the Philippine Institute of Volcanology and Seismology, said the earthquake had generated more than 2,100 aftershocks, including several reaching magnitudes of up to 6.4. Such tremors remain capable of causing further structural damage and casualties, he said.

Authorities reported that more than 3,100 homes were damaged along with 29 roads, 11 bridges and over 100 government buildings. The international airport in General Santos sustained damage and remains closed to commercial operations, although government and military flights carrying relief supplies and disaster-response personnel continue to operate.

Education officials said roughly 6,000 public school buildings in affected provinces would require safety inspections before classes could resume. The earthquake struck on the first day of the new academic term following a two-month summer break, leaving many students among those injured.

Most fatalities were attributed to falling debris from collapsed structures and landslides in General Santos and the neighboring provinces of Sarangani, South Cotabato and Davao Occidental. Authorities also reported one death linked to unusually strong sea currents generated after the quake.

The Philippine Coast Guard said seven swimmers near General Santos were swept away shortly after the earthquake. Three were rescued, one returned to shore independently, one drowned and two remain missing.

Seismologists said the earthquake originated in the Cotabato Trench, an undersea fault system off southern Mindanao. The trench was also responsible for the devastating 8.1-magnitude earthquake and tsunami in 1976 that killed about 8,000 people.

Located along the Pacific Ring of Fire, the Philippines is among the world’s most disaster-prone countries and regularly experiences earthquakes and volcanic activity due to intense tectonic movement beneath the region.

The Philippine Institute of Volcanology and Seismology said the incident occurred before nightfall on Saturday when accumulated lava on the volcano’s southwestern slope gave way, sending an avalanche of hot rocks, ash and gas downslope.

The agency’s director, Teresito Bacolcol, said the volcano has been exhibiting mild eruptive activity intermittently since January but emphasized that no explosive eruption had taken place.Authorities reported no casualties, though ash clouds spread across 87 villages in three towns, reducing visibility to near zero in some areas and disrupting road movement.

Caloy Baldo, mayor of Camalig, said residents were caught off guard by the density of the ashfall, which he described as severe enough to halt traffic along national roads.Local officials said agricultural losses were reported, particularly in vegetable farms, while livestock deaths included four water buffaloes and one cow.

Cleanup operations were underway in affected communities, including Camalig, which has a population of about 8,000 people.The volcano, rising 2,462 meters and known for its near-symmetrical cone, is among the Philippines’ most active and closely monitored.

Authorities had raised its alert status to Level 3 in January, indicating heightened unrest with potential for hazardous eruptions, including rockfalls and pyroclastic flows.Bacolcol said conditions had stabilized as of Monday but warned that the threat of further activity remained, noting that the volcano’s behavior continues to require close monitoring under the current alert level.