MANILA, March 3 (Xinhua) -- A 5.5-magnitude earthquake struck Ilocos Norte of Luzon island in northern Philippine before dawn on Sunday, the Philippine Institute of Volcanology and Seismology (Phivolcs) said.
The institute said the quake, which struck at 3:46 a.m. local time, hit at a depth of 7 km, about 44 km northwest of Burgos, a town in Ilocos Norte province.
The tremor was also felt in Pasuquin in Ilocos Norte, Vigan City in Iloco Sur province and Gonzaga in Cagayan province.
About three minutes after the initial earthquake, the institute recorded another 4.3-magnitude earthquake in Burgos town. The second tremor struck at 3:49 a.m. local time at a depth of 26 km, about 54 km northwest of Burgos.
The institute said the tremor, which was tectonic in origin, is not expected to cause any damage but aftershocks are expected.