A strong earthquake struck the South Pacific Island nation of Vanuatu on Sunday, but there were no tsunami warnings or immediate reports of damage.

The quake had a preliminary magnitude of 6.3 when it hit at 9:23 am local time, the US Geological Survey said. Its epicentre was 83 kilometres northwest of the capital, Port Vila, at a depth of 29 kilometres.

Vanessa Apuary, a Port Vila hotel worker, said the quake’s impact “wasn’t that big” considering its magnitude, which she understood to be 6.4.

“It was heavy and slow, but didn’t do any damage at all in Port Vila,” Apuary told The Associated Press.

Vanuatu sits on the Pacific “Ring of Fire,” the arc of seismic faults around the Pacific Ocean where much of the world’s earthquake and volcanic activity occurs.

A magnitude 7.7 earthquake a year ago caused a small tsunami to wash ashore at Vanuatu but no damage was reported.