Vanuatu police have impounded a ship and detained all eight crew members after one passenger was seen being dropped off at an isolated spot approximately 20 km from Port Vila.
The ship, called Retriever 1, had arrived from Fiji without the knowledge of Vanuatu Customs.
Staff from Tamanu Beach Resort say they saw a dinghy with three people aboard leave the boat and head for shore.
A man jumped from the dinghy waded ashore and was last seen heading for Port Vila.
Police have remained tight-lipped about the incident, saying they are still talking with their counterparts in Suva.
They say the ship's manifest did not include the man who is believed to be hiding somewhere on the island of Efate.
They say they confiscated a number of guns including pistols and ammunition found on the ship.
However they say one pistol is missing and is believed to have been taken by the man who came ashore in the dinghy