Planes, ships and helicopters have been mobilised to search for survivors from the MV Rabaul Queen, which sank in rough weather on Thursday with an estimated 350 people on board.  

Captain Nurur Rahman, of the country’s maritime safety authority, said the number of confirmed survivors stood at 246.  

“The search is continuing,” he said by telephone. “We are searching for survivors but now we have picked up four bodies and no survivors.”  

Rahman said he remained optimistic, given the relatively warm water, that more survivors would be found.  

The ship’s owner, Rabaul Shipping, has said it is unclear why the 47-metre ferry sank. Prime Minister Peter O’Neill has promised a full investigation into the tragedy, which occurred off the South Pacific nation’s northeast coast.  

Sea transport is a major communication lifeline in the Papua New Guinea archipelago, most of whose six million people live subsistence lives in traditional villages.