The undersea quake struck 138 kilometres (86 miles) northwest of Nuku Alofa, at a depth of 202 kilometres at 7:15 am (1915 GMT Sunday), the USGS said.
The Pacific Tsunami Warning Centre, which monitors the region and issues bulletins in the event of a tsunami being generated, had no warning in force.
The region lies in the "Pacific ring of fire", a highly active earthquake and volcanic zone that regularly experiences quakes. (*)
Editor: Kunto Wibisono
Copyright © ANTARA 2011
