At least four people have reportedly been killed after a magnitude-7.1 earthquake hit Papua New Guinea's East Sepik province.
The quake hit the remote Chambri Lake, south-west of Wewak, at a depth of 60 kilometres, just after 4am on Monday.
The temblor reportedly caused deep fissures in the land near the epicentre.
The region is marked by swamps and people tend to live subsistence lives hunting and fishing, Mathew Moihoi, the acting assistant director of the Port Moresby Geophysical Observatory, told The Associated Press.
Because of the region's remoteness and patchy communications, it could take several days to figure out the extent of the damage, he said.
A spokesman for Papua New Guinea's Natural Disaster Centre said one person had died in Wewak, while two people had died in Angoram district.
A local councillor in Angoram district, Darren Mai, said the two dead were family members.
"One of the houses fell on [my family member] and her baby boy … they died instantly," he said.
Citing local officials, the Papua New Guinea Post-Courier newspaper later reported four people had died and at least 17 more people were injured after the quake caused damage in 23 villages around the epicentre.
NGO Samaritan Aviation has been landing seaplanes on the Sepik River, where people have been taken to be flown for medical attention.
Korogu resident Colles Pinga said three houses had collapsed in his village, north of the epicentre, and families have been injured.
"Every ten minutes now we're experiencing shakes," he said on Monday morning.
"People are afraid … everything is very quiet."
"There's landslides along the riverbanks … it's quite frightening."
The Natural Disaster Centre's Colonel Carl Wrakonei said the earthquake had impacted all six districts of East Sepik.
"We cannot be able to cover the whole of six districts," he said.
"One of the challenges is mobility and accessibility, it's going to be difficult."
In a statement, Papua New Guinea's National Disaster Centre said it was conducting assessments of provinces to work out the extent of damage and casualties.
"The National Disaster Centre is currently awaiting the reports from the provinces and will provide a report on the full extent of the damage and statistics on casualties … as soon as the reports are received."
Papua New Guinea 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 7.6 quake that struck a remote area of Papua New Guinea in September was later found to have killed 21 people.
ABC/AP
