Sydney (AFP) - A powerful earthquake with a magnitude of 7.5 struck off the Solomon Islands on Sunday night, hours after a 7.6 tremor, the US Geological Survey said.
A tsunami warning was issued by the Pacific Tsunami Warning Center for the Solomon Islands, Vanuatu and Papua New Guinea, but it later cancelled the alert for all three areas.
The USGS said the quake -- which it had initially assessed at 7.7 -- occurred at 11:36pm local time (1236 GMT) at a depth of 35 kilometres (22 miles), 111 kilometres south of Kirakira in the Solomon Islands.
It said the likelihood of casualties or damage was low.
A 7.6-magnitude quake had woken the residents of the Solomons capital Honiara early on Sunday.
It struck at 7:14am, about 300 kilometres from the capital, and was followed 10 minutes later by a 5.9-magnitude aftershock.
The US Geological Survey measured the undersea quake at around 29 kilometres deep.
Honiara resident Dorothy Wickham said the National Disaster Council was warning people to stay away from low-lying areas as the islands experienced high waves.