A powerful earthquake off Mindanao in the southern Philippines generated tsunami waves around nearby coasts and triggered warnings and advisories across a wide area of the Pacific. The magnitude-7.8 quake struck at 7:37am local time, or 11:37pm GMT on Sunday, according to BBC live coverage.
The Philippine Institute of Volcanology and Seismology put the earthquake at a depth of 10 kilometres, while an account from RNZ said the US Tsunami Warning Center used a depth of 63km. The supplied reports did not reconcile those measurements. Both described the earthquake as magnitude 7.8 and located it off Mindanao.
Tsunami waves were recorded at six sites in Mindanao between 7:42am and 8:45am local time. The highest measured 1.4 metres, the Philippine institute said. The US Geological Survey also reported a half-metre wave at Davao. Philippine authorities kept their warning in place while instruments continued detecting waves and sea-level disturbances.
Measurements outside the Philippines showed smaller but still observable changes. The USGS recorded waves of about three centimetres at two locations in Palau. In Indonesia's North Sulawesi province, readings reached nine centimetres at one site and 0.8 metres at another. Indonesian authorities later lifted their warning, according to the BBC.
Advisories also extended to Guam and the Northern Mariana Islands. RNZ reported that the US warning centre forecast waves of less than 0.3 metres above tide level and warned of hazardous currents and changing water levels around beaches, harbours and nearshore areas. Officials said fluctuations could reach Guam from 12:45pm local time before moving north towards Rota, Tinian and Saipan.
Emergency authorities stressed that no general evacuation had been ordered for Guam or the Northern Marianas. Residents and visitors were instead told to remain out of the water and away from beaches, harbours and shorelines until the advisory ended. Forecast effects included limited flooding around some beaches and harbours, as well as unusual currents that could persist for hours. RNZ noted that the first wave would not necessarily be the largest and that actual arrival times could vary.
The Straits Times reported that tsunami warnings had also been triggered in Japan, Indonesia and Guam before being lifted later in the afternoon. The supplied extracts confirm warnings in those places but do not establish that a measurable tsunami wave reached either Japan or Guam.
On Mindanao, the earthquake caused buildings to collapse or sustain damage and produced a long sequence of aftershocks. The Philippine institute counted 138 aftershocks by 11am, ranging in magnitude from 1.3 to 6.7, according to the BBC. The quake was also felt in Indonesia's North Sulawesi province, more than 200km from the epicentre.
Casualty reports changed rapidly during the day. BBC live coverage moved from early reports of one and three deaths to an official count of 15, then cited a civil-defence spokesperson who said 19 deaths had been reported, seven people were missing and the fatality count still required verification by the national disaster agency. A later Straits Times recap headline reported at least 32 deaths. Because those updates differ in timing and validation, no single final toll can be established from the supplied extracts.
President Ferdinand Marcos Jr directed government agencies to respond immediately and urged people in exposed areas to move to higher ground. Officials also warned residents not to re-enter visibly damaged buildings. The quake occurred in a highly active seismic area facing the Cotabato Trench, which Philippine government scientists describe as capable of producing earthquakes across a wide range of magnitudes.
The alerts across several countries showed how an offshore earthquake can create hazards far beyond the area of strongest shaking. Recorded waves varied substantially by location, while emergency agencies adjusted their advice as new sea-level readings arrived.
