Manila, May 27 (Reporter) An earthquake with a preliminary magnitude of 5.1 struck Quezon province, east of Manila, on Tuesday, the Philippine Institute of Volcanology and Seismology reported. The institute said the quake, which occurred at 12:17 p.m. local time, hit at a depth of six kilometers, about 24 kilometers northwest of General Nakar in Quezpn province. The institute warned that the tectonic quake will trigger aftershocks and cause damage. The tremor also shook the Philippine capital. The Philippines has frequent seismic activities due to its location along the Pacific "Ring of Fire...////...