At least 12 people have died in the Solomon Islands after a tsunami swept ashore following a strong undersea earthquake in the South Pacific.

The main town in the western Solomons, Gizo, was hit by waves several metres high that swamped buildings and washed people out to sea, officials said.

Local officials fear the numbers of dead could rise, with reports of outlying villages being destroyed.

The quake measured 8.0 and hit at 0740 local time on Monday (2040 GMT Sunday).