MANILA, Philippines >> Scientists say a magnitude 5.9 earthquake has hit the northern Philippines but caused no damage or injuries and no destructive tsunami was generated.

The Philippine Institute of Volcanology and Seismology says the tremor struck at 1:15 a.m. Tuesday and was centered 19 miles under the sea about 22 miles  off Iba township in Zambales province.

The institute has recorded at least three aftershocks with magnitudes 2.8 to 4.0. It says the quake was generated by the Manila Trench that runs north to south off the western coast of the main island of Luzon.

The Philippines is within the Pacific Ring of Fire where earthquakes and volcanic activity is common.