A 6.7-magnitude earthquake struck Papua New Guinea Thursday, the US Geological Survey reported, but seismologists said while it was widely felt it was too deep to cause much damage.

The quake hit some 62 kilometers (39 miles) from the Eastern Highlands provincial capital Goroka and 324 kilometers from the national capital Port Moresby at a depth of 105 kilometres.

More than 100 missing passengers were feared trapped inside an overloaded ferry when it sank off Papua New Guinea, a maritime official said Friday as rescuers scoured the ocean for more survivors.

So far, 246 people have been plucked to safety in a joint rescue operation conducted by PNG and neighboring Australia after the MV Rabaul Queen sank on Thursday morning.

More than 200 people were plucked from waters off Papua New Guinea Thursday after a ferry sank but many others remained missing, with rescuers scouring the area for survivors as night fell.

Operator Star Ships said it lost contact with the MV Rabaul Queen at about 6am on Thursday (2000 GMT Wednesday) while it was travelling between Kimbe and Lae in the east of the Pacific nation, blaming "bad weather" for the disaster.

With voices hardly louder than an insect's buzz, the tiniest frogs ever discovered are smaller than a coin and hop about the rainforest of the tropical island of Papua New Guinea, U.S. scientists said Wednesday.

Not only are these little peepers with the big names -- Paedophryne amauensis and Paedophryne swiftorum -- the smallest frogs known to man, they are also believed to be the smallest vertebrates on Earth, said the report in the science journal PLoS ONE.

A 6.3-magnitude earthquake rocked Papua New Guinea's remote New Britain region on Tuesday, but was unlikely to cause a tsunami, Australian seismologists said.

The US Geological Survey said the quake occurred at a depth of 10 kilometers, about 163 kilometers east-northeast of Kandrian, New Britain and some 576 kilometers from the capital Port Moresby.

Papua New Guinean officials were Friday trying to piece together how a passenger plane crashed in dense forest, killing 28 people -- but leaving four survivors -- in the nation's worst air disaster.

The survivors were the Australian and New Zealand pilots, a flight attendant, and a passenger believed to be a Chinese national, who reportedly escaped the fiery wreckage through a crack in the fuselage.

A French diplomat working for the European Union in Papua New Guinea was airlifted to Australia on Monday after a shark attacked him when he was kite-surfing near Port Moresby.

Thomas Viot, 30, was bitten on the right leg by what he believed was a two-meter tiger shark on a reef at Hula, south of the PNG capital on Sunday afternoon.

Who will speak Iniai in 2050? Or Faiwol? Moskona? Wahgi? Probably no-one, as the languages of New Guinea -- the world's greatest linguistic reservoir -- are disappearing in a tide of indifference.

Yoseph Wally, an anthropologist at Cendrawasih University in Jayapura keeps his ears open when he visits villages to hear what language the locals are speaking.

For decades, the only foreign visitors to venture into Papua were gold-diggers, anthropologists, missionaries and soldiers fighting imperial wars.

But the vast, western half of New Guinea island is slowly opening its doors to tourists as a "hidden paradise", a land of ancient tribal cultures, glittering reefs, soaring glaciers and teeming wildlife.

A frog with fangs, a blind snake and a round-headed dolphin are among more than 1,000 new species recently found on the incredible Melanesian island of New Guinea, environment group WWF said.

Scientists made the astounding discoveries, which also included a river shark and dozens of butterflies, on New Guinea at a rate of two a week from 1998 to 2008, WWF said in a new report on the island's natural habitat.