MOSCOW (Sputnik) – The quake struck at 22:50 GMT on Friday about 73 kilometers (45 miles) south of Vanuatu’s second largest city, Luganville, USGS said.
There were no immediate reports of damage or casualties. No tsunami warning was issued.
On Thursday, a 7.3-magnitude earthquake occurred off the Vanuatu coast.
The Vanuatu Islands are part of the so-called Pacific Ring of Fire quake zone, where about 90 percent of the world's earthquakes occur.