Strong, shallow underwater earthquakes shook western Indonesia and the Philippine capital region Monday but no serious damage was immediately reported and no tsunami warnings were issued.

In Indonesia, a magnitude-6.7 quake that was 16 kilometres deep struck about 169 kilometres west of Pariaman, a town in West Sumatra province, the US Geological Survey said.

The Indonesian Meteorology and Geophysics Agency said the quake was felt in many parts of the province but there was no danger of a tsunami. It was occurred just before dawn and was centred about 161 kilometres southeast of South Nias, a district in North Sumatra province.

A 6.4-magnitude earthquake also shook parts of the Philippine capital region and outlying provinces at dawn but there were no reported damages or injuries, the Philippine Institute of Volcanology and Seismology said.

The offshore quake was set off by movement along the Manila Trench and its epicenter was about 110 kilometres west of Lubang island in Occidental Mindoro province, which lies south of Manila, the Philippine institute said. Its depth was about 28 kilometres.

Indonesia and the Philippines lie along the Pacific “Ring of Fire” — a line of seismic faults around the Pacific Ocean — and are frequently struck by earthquakes and volcanic eruptions.

A 6.2 earthquake shook Indonesia's West Sumatra province last month, killing at least 16 people and injuring more than 400. Thousands of homes and other buildings were damaged by the tremors that were felt as far away as Malaysia and Singapore.?