Maritime authorities hope they will know soon who was at fault when a mystery ship rammed a yacht off Northland in November.
The ship disappeared without answering mayday calls after the Swedish yacht Mica was rammed 30 nautical miles northeast of Cape Reinga on November 9.
The yacht sank quickly and ownerAlf Jaselius, 52, drifted in a liferaft in heavy seas for several hours before he was rescued by a Russian ship.
The Maritime Safety Authority has refused to name the ship and says until the crew can be interviewed it cannot establish if the ship did anything wrong.
Authority director Russell Kilvington said within a day or two of the ramming that there was a good chance the ship had no idea it had hit the yacht.
But he said it was puzzling that it had not answered Mica's mayday calls.
Yesterday Mr Kilvington said the incident was in international waters and although the authority investigation had no legal mandate, it hoped to know more soon.
"It is still on the boil."
Asked if he was confident the captain or crew would be charged over the incident, Mr Kilvington said: "We believe we will able to get more information about the ship and from the people on board the ship.
"The investigation is continuing. We are not letting it drop and we believe that we will be able to get more information in due course.
"It is outside our waters and we have got to push and pressure and cajole people and we are having some success there so I am reasonably confident.
"Until the people have been interviewed we are not sure there is necessarily a case to answer.
"We are not throwing guilt at anybody but we do need to know exactly what has happened."
