The quake, which hit at 10:58 am (0158 GMT), was centred 33 kilometres (21 miles) under the ground some 185 kilometres south-west of the Papua capital of Jayapura, meteorology headquarters official Adjat said.
The Indonesian archipelago sits on the Pacific Ring of Fire where continental plates meet, causing frequent seismic and volcanic activity.
Indonesia was the nation worst hit by the earthquake-triggered Asian tsunami in December 2004, which killed some 168,000 people in Aceh province.
A 7.7-magnitude earthquake in July on the south coast of the main island of Java also killed more than 600 people.

Copyright AFP (Agence France-Presse), 2006