Another temblor may be in the offing along the Philippine Fault Zone which generated last week’s 6.7 magnitude earthquake off Surigao del Norte province. Movement of PFZ’s Surigao segment triggered such earthquake and may have also “disturbed” any of the adjacent Leyte and Mindanao segments, possibly increasing chance for a new temblor there, noted science research specialist Rhommel Grutas from Philippine Institute of Volcanology and Seismology .