At least one body was recovered while more than 30 people are missing after an inter-island ferry sank off the South Pacific island nation of Vanuatu, the prime minister’s office said on Sunday.

Of the more than 40 crew members and passengers on board, 15 people have been accounted for alive, according to a statement on US social media platform Facebook.

The statement, citing Luganville MP Matai Seremiah, said the search in open waters is being scaled back as efforts shifted to the southeast coast, where currents may have carried survivors.

“The loss appears to be the result of strong winds and marine warnings not being heeded, and possibly of negligence including overloading of the vessel,” said the prime minister’s office.

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It urged ship owners to prioritize safety, ensure vessels are seaworthy and properly equipped, and maintain reliable communication systems.

“Ignoring strong marine warnings puts lives at risk,” it said, adding that a full investigation would be done to establish the facts and prevent a recurrence.

The vessel, the MV Matui, was carrying 47 people, including crew members, from Santo to Ambae on Saturday, according to the Vanuatu Broadcasting & Television Corporation.