Tsunami threat passes after 7.5 PNG quake

A 7.5-magnitude earthquake has struck off the coast of Papua New Guinea, sending startled residents fleeing from their homes, but a tsunami threat has passed with no immediate reports of major damage.

The quake hit on Monday at a depth of 33 kilometres, some 55km from the nearest city of Kokopo on New Britain island and 787km from the capital Port Moresby, the United States Geological Survey said.

The Pacific Tsunami Warning Centre initially cautioned that "hazardous" tsunami waves could hit some coastal areas in PNG. It later updated its advice to say the threat had passed.

It noted a reading of waves 0.03 metres above the tide level at Tarekukure Wharf, some 450 kilometres from the epicentre. Information from coastal areas closer to where the quake struck was sketchy.

Mathew Moihoi from Papua New Guinea's Geological Observatory said officials were still unable to make contact with more remote areas to determine whether there had been any sea level changes.

"We've not been able to receive such information from the people as to whether a tsunami has been observed or not," he said.

Leonie Fakal, a housekeeper at the Seaview Beach Resort in Kokopo, said all the staff and their two guests ran outside when the quake hit.

"Everybody was a bit afraid. There was a lot of shaking and some things fell down in the hotel," she told AFP soon after the quake.

"Everyone ran outside but there was not much damage."

John Amos, a reception clerk at the Kokopo Beach Bungalow Resort, added that the quake produced a powerful jolt but there was no damage.

"It was the biggest earthquake we have experienced so far," he said.

"We had one big one and then some smaller wobbles. But we seem to be quite ok. There is no damage and it's quiet here now."

He added that staff were "keeping an eye on the beach" for any unusual ocean activity.

The initial quake was followed by a smaller 5.7-magnitude aftershock in the same area.