Vanuatu earthquake: Powerful 6.4 magnitude quake hits off Pacific island chain's coast

The US Geological Survey said it struck in the centre of Erromago

Vanuatu archipelago is just over 1,000 miles off the coast of Australia (USGS)

An earthquake measuring 6.4 on the Richter scale has struck off the Vanuatu archipelago in the Pacific Ocean.

The US Geological Survey said it struck in the centre of Erromago, the fourth largest island, which has a population of just under 2,000 people.

But its depth of 124.4 miles would have dampened its effect, it said, and there have been no immediate reports of casualties or damage.

The Pacific Tsunami Warning Center said the quake currently did not pose a tsunami threat

Situated to the east of Australia, the island chain is in the so called "Ring of Fire", which is prone to earthquakes.

It was the fourth major earthquake to strike around the world in the last 24 hours - following one in Mexico that measured a magnitude of 7.1, a 6.1 magnitude earthquake in New Zealand and another one with a magnitude of 6.1 striking off the coast of Japan - around 200 miles east of Fukushima.

The Japanese quake comes just six years after a tsunami sparked by an earthquake in the Pacific hit the nuclear plant in Fukushima, causing a major disaster - with the water disabling the emergency generators required to cool the reactors at the plant after they had automatically shut down.

The disaster claimed the lives of 15,894 deaths, left over 6,000 injured and more than 2,500 people missing.

Millions of homes were destroyed and millions of families were evacuated from the area surrounding the Fukushima plant and many are yet to return as there are still concerns about the effect of radiation in the atmosphere.

The incident lead to Japan closing all 54 of its nuclear plants for a time but five are now back online.

Additional reporting by agencies