A 6.3-magnitude offshore earthquake struck Davao Occidental province in the southern Philippines early Thursday, marking the second strong tremor to hit the region in less than 24 hours, according to the Philippine Institute of Volcanology and Seismology (Phivolcs).

The tectonic earthquake occurred at 5:41 a.m. local time at a depth of 10 km, with its epicentre located about 99 km southwest of Balut Island off the coast of Davao Occidental province, the institute said.