Manila, Philippines. A powerful offshore earthquake collapsed walls of houses and buildings late Tuesday in the central Philippines, killing at least 31 people, injuring dozens more, and plunging communities into darkness as the shaking knocked out power, officials said.

The magnitude 6.9 quake struck at a depth of 5 kilometers (3 miles), about 19 kilometers (12 miles) northeast of Bogo, a coastal city of 90,000 people in Cebu province, where at least 14 residents died, local disaster official Rex Ygot told The Associated Press. He warned the death toll could rise as rescuers struggled to reach a landslide site in a mountain village.

“It’s hard to move in the area because there are hazards,” said Glenn Ursal, another disaster-mitigation officer, adding that survivors had been rushed to hospitals.

In nearby Medellin town, at least 12 people were killed when ceilings and walls collapsed on them while they slept, according to local disaster chief Gemma Villamor. In San Remigio, five people --including three coast guard personnel, a firefighter, and a child-- died when walls caved in as they tried to flee a basketball game disrupted by the quake, Vice Mayor Alfie Reynes told DZMM radio. Reynes appealed for food and clean water, saying the town’s water system had been damaged.

The quake also damaged a fire station, roads, and an old Catholic church in Daanbantayan, officials said. Firefighter Rey Cañete described rushing outside with colleagues only to stumble from the violent shaking. A wall in their station collapsed, injuring several residents who were later treated for cuts and bruises.

Hundreds of frightened residents in Bogo gathered in open fields overnight, refusing to return to their homes. Several businesses showed visible damage, while asphalt and concrete roads split with deep cracks.

Cebu Gov. Pamela Baricuatro said the full extent of the destruction in northern Cebu would not be clear until daylight. “It could be worse than we think,” she said in a video message.

The Philippine Institute of Volcanology and Seismology initially issued a tsunami warning for Cebu and the nearby provinces of Leyte and Biliran, advising residents to stay away from coastlines. The advisory was lifted later after no unusual waves were detected.

The quake struck as Cebu and nearby provinces were still reeling from a tropical storm that battered the central Philippines on Friday, killing at least 27 people, knocking out power, and forcing tens of thousands to evacuate.

The Philippines, one of the world’s most disaster-prone countries, sits on the Pacific “Ring of Fire,” an arc of seismic faults where earthquakes and volcanic eruptions frequently occur. The country is also hit by about 20 typhoons and storms each year.