The earthquake was registered 203 km southwest of Nabire, Indonesia.
The epicentre was located at a depth of 12.87 kilometres, according to the European Mediterranean Seismological Centre (EMSC).
No damage or casualties have been reported so far.
Indonesia is located in a seismically active zone known as the Ring of Fire and regularly suffers from powerful earthquakes. Hundreds of thousands of people died in 2004 when some 9.2 magnitude earthquake hit Sumatra's Aceh region, triggering a tsunami in several states bordering the Indian Ocean.