A tsunami warning has been issued for Papua New Guinea and island nations in the south-west Pacific after a 7.8-magnitude earthquake off Vanuatu.
The epicentre was 295km (180 miles) north-northwest of Vanuatu’s largest island, Santo, at a depth of 35km (21.7 miles), the US Geological Survey said.
There have so far been no immediate reports of injuries of damage.
More than 170 people died last week when a tsunami triggered by an quake hit Samoa, American Samoa and Tonga.
Earlier on Wednesday, a 6.7-magnitude quake struck off the Philippines, but no tsunami warning was issued.
Shortly after the earthquake off Vanuatu struck at 2203 GMT, the Pacific Region Headquarters of the US National Weather Service said a tsunami warning was in effect for Vanuatu, the Solomon Islands, Nauru, Papua New Guinea, Tuvalu, New Caledonia, Fiji, Kiribati, Kosrae, Wallis and Futuna, and the Howland and Baker islands.
Masalai blog 
By Ilya Gridneff, Papua New Guinea Correspondent. PORT MORESBY, Oct 8 AAP
When Mother Nature roared Papua New Guinea’s workforce hit the door.
The central business district in PNG’s capital Port Moresby was evacuated on Thursday amid fears a tsunami might strike but for most workers it simply became a free afternoon off.
PNG and the Solomon Islands were on full alert after powerful earthquakes to the southeast rocked the island nation of Vanuatu, sparking tsunami warnings across the Pacific region.
The news sent shockwaves through PNG, with workers in a panic.
When the Pacific Tsunami Warning Centre later cancelled any threat of tsunamis hitting Pacific countries, PNG residents did not return from the hills they had run to.
Management at Deloitte Tower, Port Moresby’s tallest building, told staff to leave at about 10.30am (1130 AEDT).
Other companies in nearby buildings followed suit, telling staff to evacuate.
Street traders also made a quick exit as the Port Moresby centre became a hive of frantic activity.
“There was panic on the streets,” Kila Kila, who works in Deloitte Tower, told AAP.
“Everybody was running around, running for buses.
“Next door the bank staff evacuated their building and people were streaming out of other offices,” she said.
“Over the building intercom, management told people to remain calm but to leave the building.
“About five minutes later they then said over the speakers the warning had been cancelled but everyone had already gone and it didn’t look like returning to work today,” she said.
John, a trader in Kokopo, East New Britain Province in PNG’s north said the small town had virtually shut down.
“They all knew pretty quick about the threat, they all know the warning is off but didn’t return to work,” he said.
It wasn’t just local staff who took advantage of the massive quakes.
Scores of expatriates in Port Moresby flocked to the Royal Papuan Yacht Club and other popular watering holes for a share in the panic – over a beverage or two.
AAP ig/ht/apm