More than 200 passengers have been rescued from a ferry that sank early Thursday off the northern coast of Papua New Guinea.

Nerae Marimahu, a spokeswoman with the Pacific nation's National Maritime Safety Authority in Port Moresby, told VOA the MV Rabaul Queen sank about 16 kilometers off Cape Fortification. She said it was not immediately clear why the ferry sank.

The maritime agency says at least 300 passengers were believed to aboard the ferry when is sank.

Australia, which is aiding in the rescue effort, says at least 219 people have been pulled alive from the waters.

The ferry's operator says it lost contact with the vessel as it was traveling between the island of New Britain and the town of Lae.

Search and rescue ships and crews were searching for survivors.

Australian Prime Minister Julia Gillard described the disaster as “a major tragedy” and said her country was helping Papua New Guinea respond.