A magnitude-6.2 earthquake struck off the coast of Tonga on Thursday, the United States Geological Survey (USGS) said.
It comes almost two weeks after the Pacific kingdom was devastated by a volcanic eruption and tsunami.
The earthquake struck about 250 kilometres off the main island of Nuku'alofa at a depth of 14 kilometres, the USGS said.
There were no immediate reports of damage. However, communication is still limited with Tonga after the eruption severed the main communications cable.
The eruption of the Hunga-Tonga-Hunga-Ha'apai volcano in Tonga on January 15 killed three people, blanketed the Pacific nation in volcanic ash and sent a tsunami across the wider Pacific.