MANILA, Philippines -- Philippine seismologists say a magnitude-6 earthquake has jolted the capital, Manila, rousing people from their sleep. There are no immediate reports of damage or injuries.
Renato Solidum of the Philippine Institute of Volcanology and Seismology said the pre-dawn quake was centered under the sea about 27 miles (43 kilometers) southwest of the town of San Antonio in the northwestern province of Zambales, but was too deep under the seabed to cause any significant damage or casualties.
Solidum says aftershocks are expected, adding the quake was also felt across the main northern Luzon island.
The Philippine archipelago lies in the Pacific "Ring of Fire," where earthquakes and volcanic activities are common.
A magnitude-7.7 quake killed nearly 2,000 people in Luzon in 1990.