The US Geological Survey said there were two earthquakes - measuring magnitude 7.0 and 7.1. Other reports suggested there had been three quakes.

The earthquakes were powerful enough to set off tsunamis, the Japan Meteorological Agency said.

"The quake is able to trigger a one-meter high tsunami that would be on course to hit Basco in the Philippines," an agency official said.

"But since it's been nearly two hours since the quake without any tsunami being observed, the possibility is declining. We'll keep monitoring the area for the time being," he said.

The Pacific Tsunami Warning Center earlier issued a tsunami bulletin saying that earthquakes of the size "sometimes generate local tsunamis" but saying there was "no destructive Pacific-wide tsunami threat".

Agence France-Presse