Reymundo Punongbayan, director of the Philippine Institute of Volcanology and Seismology (Phivolcs), however, went on television yesterday to assure the public that the worst is over.
"They will be shaken a little bit by the aftershocks but no big one that will (cause) tsunami (tidal waves), no big one that will cause buildings to collapse," he said, as officials asked more than 27,000 displaced residents to return to their homes.
Melchor Rosales, administrator of the the Camp Aguinaldo-based Office of Civil Defense, told ABS-CBN television apparently not all people who fled coastal areas for fear of tsunamis have gone back.
"They expected that a tsunami will follow (the earthquake)," he said. "Fortunately, for us the water was not that high, but a precautionary evacuation was undertaken."
For such a strong earthquake, the damage was not that extensive and rescuers reported only 76 destroyed or damaged homes, he added.
The earthquake exacted the heaviest toll on tiny towns around the Rio Grande river basin near the epicenter, causing widespread power outages that affected many of Mindanao’s 18 million people.
Most of the deaths were caused by falling debris but also included four cases of heart attacks at the height of the tremor.
During the earthquake, two old churches were also toppled, cracks ripped buildings and the seas off some coastal towns swelled by three meters.
Residents feared that Mt. Parker volcano, near the epicenter of the earthquake, might erupt after parts of its crater walls collapsed, releasing tons of water that washed away homes.
Almost 28,000 people in Sarangani province, the worst hit, spent the night at makeshift emergency shelters in an elementary school, churches and social halls.
Ousted President Joseph Estrada said in a statement yesterday he has asked Sen. Luisa "Loi" Ejercito Estrada and some friends to launch a relief operation to help the earthquake victims rebuild their lives.
"I also call on our people to do their civic duty and for the people of Mindanao especially, regardless of religious and political belief, to unite and be counted to do their part to help our countrymen," he said in a statement.
"Even as I am confident that the concerned government agencies are already doing their share to mitigate the impact of this new calamity, I have asked my wife, Sen. Dra. Loi Estrada, and some friends to take some time to help the victims rebuild their lives by undertaking a much-needed relief operation."– Jose Rodel Clapano