The U.S. Geological Survey says a 6.2-magnitude earthquake struck the coast of Fiji this morning.
There were no immediate reports of casualties or damage after the quake hit just after 4 o'clock.
The Associated Press says the quake was centered 145 kilometres northeast of Labasa on the island of Vanua Levu at a depth of 10 kilometres.
Vanua Levu is the second largest of the Fiji islands.
Meanwhile, two strong quakes of magnitude 6.4 struck off Tonga this morning.
The quakes, which hit a minute apart around 5:15 a.m. local time were centered about 640 km northwest of Tonga's second largest town Neiafu.
The quakes were at a depth of 33 km.