An earthquake measuring 6.6 magnitude on the Richter Scale struck off the Pacific island nation of Vanuatu on Sunday, the United States Geological Survey (USGS) said. 
The shallow quake struck 101 kilometers (63 miles) southwest of the town of Isangel on Tanna island, USGS said. 
There were no immediate reports of damage or casualties, and no tsunami warning was issued. 
Vanuatu is part of the "Ring of Fire", a zone of tectonic activity around the Pacific that is subject to frequent earthquakes and volcanic eruptions. 
Vanuatu has been rocked by a series of quakes this year, including some that prompted tsunami warnings. 

Source : QNA