A series of powerful earthquakes in Indonesia have killed at least four people and injured dozens of others.

The quakes in the remote eastern part of the country also cut power lines and badly damaged buildings in the area.

One of the earthquakes - a 7.3-magnitude tremor - sent small tsunamis into Japan's southeastern coast, but there were no reports of damage there and no tsunamis in Indonesia's Papua area.

The strongest 7.6-magnitude quake occurred early Sunday morning with its epicenter at a depth of 48 km beneath the seabed.

Sujabar is an earthquake information officer.

"The earthquake was powerful. It's normal in the Papua area that it will be followed by many aftershocks. Up to 11 am local time on Sunday, we had recorded 45 aftershocks. The last one we have recorded measured 4.6 on the Richter scale."

The airport runway nearest the epicenter was cracked, and commercial flights to the area were canceled.

A search for possible survivors is under way.

Indonesia straddles a chain of fault lines and volcanoes known as the Pacific "Ring of Fire" and is prone to seismic activity.