A magnitude 6.3 earthquake hit Pacific nation Vanuatu on Sunday, the United States Geological Survey said, but was not expected to generate a tsunami.
The quake occurred at 9:23 am local time at a depth of about 29 kilometres (18 miles), the USGS said, centred in a patch of ocean about 83 kilometres (51 miles) northwest of Vanuatu's capital Port Vila.
Striking near a sparsely populated cluster of islands, the Pacific Tsunami Warning Centre said "the earthquake is not expected to generate a tsunami".
There were no immediate reports of damage in Vanuatu.
Earthquakes are common in Vanuatu, a low-lying archipelago of 320,000 people that straddles the seismic Ring of Fire.
The Ring of Fire is an arc of intense tectonic activity that stretches through Southeast Asia and across the Pacific basin.