DAVAO - A strong earthquake jolted the southern Philippines yesterday, killing at least one person and causing a three-storey building to collapse, setting off a search for people feared to have been trapped inside, officials said.
The magnitude-6.8 quake was centred 61km south-west of Davao on the island of Mindanao, at a depth of 28.2km, the United States Geological Survey said, revising down the magnitude from an earlier 6.9.
The Pacific Tsunami Warning Centre said there was no tsunami threat from the quake, based on available data.
A child was killed in a village in Davao del Sur's Matanao town when a wall of her house collapsed and hit her on the head, officials said.
Davao del Sur Governor Douglas Cagas said a three-storey building housing a grocery store collapsed in downtown Padada during the quake, trapping an unspecified number of people inside.
Search and rescue efforts were under way, he told DZMM radio network, adding that an unknown number of people were injured in his province.
"I saw the building when it fell," Padada resident Leighton Angcan told Reuters. "It was the tallest here and it was really destroyed. I saw people running outside."
Video footage posted by users on Twitter showed overhead electrical wires swaying and erupting in a shower of sparks. Another clip showed water sloshing out of a hotel swimming pool.
Matanao Mayor Vincent Fernandez said his two-storey town hall was badly damaged by the intense shaking, along with two bridges and several buildings already weakened by previous quakes.
"The shaking was different this time, it wasn't swaying. It's like a roller was rumbling by underneath," Mr Fernandez told DZMM from an emergency shelter.
As he was being interviewed, he paused briefly, saying the ground was shaking again in the latest of dozens of aftershocks.
Mr Fernandez appealed for food packs and tents for residents who needed immediate shelter from the rainy weather.
Many buildings that could have been used as evacuation centres have been damaged by recent earthquakes, he said.
President Rodrigo Duterte was safe with his daughter in his house in Davao city, where the earthquake was felt strongly. He returned to sleep after the tremors, said Brigadier-General Jose Niembra, who heads the presidential security force.
Presidential spokesman Salvador Panelo said: "He is okay. He and his daughter Kitty were in their house when the quake struck.
"First Lady Honeylet was on her way home when the ground trembled. She said her car was swaying. She is unhurt."
The Philippine Institute of Volcanology and Seismology said aftershocks could be expected.
Several strong aftershocks were recorded after the main tremor, the strongest a magnitude-5.7 one centred north of General Santos City.
Classes in Davao del Sur province will be suspended today to allow checks on the stability of school buildings.
Some cities and towns have lost power, officials said.
The Davao region has been hit by several earthquakes in recent months, causing some deaths and scores of injuries and badly damaging houses, hotels, malls and hospitals.
The Philippine archipelago lies on the so-called Pacific Ring of Fire, an arc of faults around the Pacific Ocean where most of the world's earthquakes occur.
It is also lashed by about 20 typhoons and other severe storms each year, making the South-east Asian nation of more than 100 million people one of the world's most disaster-prone countries.