A POWERFUL earthquake struck near the Philippine city of Davao on Sunday afternoon, the US Geological Survey said, hurting several people and damaging major buildings. No tsunami alert was issued.

The magnitude 6.8 quake was centred 61 kilometers southwest of Davao on the island of Mindanao, at a depth of 28.2 km, the USGS said, revising down the magnitude from an earlier 6.9.

The Philippines lies in the so-called Pacific “Ring of Fire,” an arc of intense seismic activity around the Pacific Ocean where most of the world’s earthquakes strike.

The Pacific Tsunami Warning Center said there was no tsunami threat from the quake, based on available data.

“So devastating,” said Anthony Allada, information officer of Magsaysay, Davao del Sur said of the temblor.

The Philippine Institute of Volcanology and Seismology (Phivolcs) said damage and aftershocks could be expected.

Two strong aftershocks of magnitude 5 and 5.7 centred north of General Santos City was recorded after the main tremor.

State-run Philippine Information Agency said several shoppers and employees were likely trapped inside a three-floor commercial shopping center that collapsed in Padada, Davao del Sur province.

Municipal Disaster Risk Reduction Management Officer Luke Cadoyas said four people near the building were injured.

Power was out in General Santos City, where patients at a local hospital were being evacuated, radio DZMM reported.

Video footage of the latest quake posted by users on Twitter showed overhead electrical wires swaying and erupting in a shower of sparks. Another video showed water sloshing out of a residential swimming pool.

One picture said to be from Padada, close to the epicentre in the province of Davao del Sur, showed a building collapsed onto a car.

Several local governments including Davao City suspended classes for Monday to give way to building inspections.

Brownouts were reported in several areas, but the National Grid Corporation of the Philippines said the Mindanao grid “remains intact” and “there were no reports of damage to transmission facilities in Davao del Sur and nearby areas where the earthquake was felt.”

Mindanao was shaken by three powerful quakes in October, which together killed more than 20 people. The quakes hurt more than 500 people and affected more than 70,000 families, according to the national disaster agency. 11 people were still missing, it said.

Another magnitude 5.9 earthquake on Nov. 18, with an epicenter in Bukidnon, did not cause any major damage or deaths.

As of end-November, more than 13,000 families were still in 107 evacuation centers, according to the agency.

The highest reported intensity for the Sunday quake at 7 was recorded in the towns of Magsaysay and Matanao, while intensity 6 was felt in the cities of Kidapawan, Koronadal and General Santos, and the towns of Bansalan in Davao del Sur, and Alabel and Malapatan in Sarangani province. — Reuters and Carmelito Q. Francisco