MANILA, Nov. 29 (Xinhua) -- An offshore earthquake, measuring 5.9 magnitude, jolted southern Philippines Sunday morning. There is not yet report of casualties or damage.

    The Philippine Institute of Volcanology and Seismology (Phivolcs) said the temblor with a tectonic origin struck at 2:10 a.m. Sunday (1810 GMT Saturday) 159 kilometers southeast of General Santos city.

    The Southeast Asian country is part of the so-called Pacific Ring of Fire, a string of islands on the Pacific Ocean rim that were formed by the eruptions of undersea volcanoes.