An earthquake of magnitude 6.7 struck off Papua New Guinea's New Britain Island on Friday evening.
Rabaul, Papua New Guinea. Photo: Alex Smith
The United States Geological Survey says the quake was 128 kilometres south-southwest of Rabaul at a depth of 61 kilometres.
The Pacific Tsunami Centre says there are no tsunami warnings.
However, disaster authorties in PNG say there is a possibility of small, localised tsunamis and people in the northern islands region have been asked to remain alert.
A reporter for the National Broadcasting Corporation in Rabaul says the earthquake was large, but doesn't appear to have caused any significant damage in a region used to large quakes.
A 6.7 magnitude earthquake struck in the same area yesterday.
The NBC reporter says a wave caused by that quake damaged a coastal road leading in to Rabaul.