The death toll was expected to rise from the 6.9 magnitude quake that struck late on Tuesday and trapped an unspecified number of residents in the hard-hit city of Bogo and outlying rural towns in Cebu province.
Sporadic rain and damaged bridges and roads hampered the race to save lives on Thursday.
On Wednesday night, rescuers in orange and yellow hard hats used spotlights, a backhoe and bare hands to sift through the rubble of concrete slabs, broken wood and twisted iron bars for hours in a collapsed building in Bogo city. No survivor was found.
"We're still in the golden hour of our search and rescue," Office of Civil Defence deputy administrator Bernardo Rafaelito Alejandro IV said.
"There are still many reports of people who were pinned or hit by debris."
The earthquake occurred at a dangerously shallow depth of 5km and was centred about 19km northeast of Bogo, a coastal city of about 90,000 people in Cebu province where officials reported about half of the known deaths.
The Philippine government is considering whether to seek help from foreign governments based on an ongoing rapid damage assessment, Alejandro said.
Workers were trying to transport a backhoe to hasten search and rescue efforts in a cluster of shanties in a mountain village hit by a landslide and boulders, Bogo city disaster-mitigation officer Rex Ygot told The Associated Press.
"It's hard to move in the area because there are hazards," said Glenn Ursal, another disaster mitigation officer, who added that some survivors were brought to a hospital from the mountain village.
Deaths also were reported from the outlying towns of Medellin and San Remigio, where three coast guard personnel, a firefighter and a child were killed separately by collapsing walls and falling debris while trying to flee to safety from a basketball game in a sports complex that was disrupted by the quake, town officials said.
The quake was one of the most powerful to batter the central region in more than a decade and it struck while many people slept or were at home.
The Philippine Institute of Volcanology and Seismology briefly issued a tsunami warning for the coastlines of Cebu and the nearby provinces of Leyte and Biliran, but the warning was lifted within hours.
Still, thousands of traumatised residents refused to return home and chose to stay in open grassy fields and parks overnight despite intermittent rains.
Cebu and other provinces were still recovering from a tropical storm that battered the central region last Friday, leaving at least 27 people dead mostly due to drownings and falling trees, knocking out power in entire cities and towns and forcing the evacuation of tens of thousands of people.
with AP
