MANILA, Philippines (AP) - A strong earthquake rocked a group of islands between the northern Philippines and Taiwan, causing aftershocks but no reports of damage or casualties.

The U.S. Geological Survey says Sunday night's undersea quake in the Luzon Strait, centered about 70 miles northwest of Basco town in Batanes islands, registered 6.1. It was followed by a 4.6-magnitude aftershock.

The Philippine seismological agency put the magnitude of the first quake at 6.0 and said it struck at 10:58 p.m. Sunday.

The sparsely populated rocky islands are frequently shaken by temblors. The Philippine archipelago lies in the so-called Pacific Ring of Fire, where quakes are common.

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