The ship ran out of fuel and, battered by bad weather, eventually sank.
Twenty-six people were missing on Saturday after the shipwreck on Thursday of a ferry in the Makassar Strait, which separates the islands of Sulawesi and Borneo, in Indonesia.
The news was only known to the authorities two days later, the head of the emergency services, Djuanidi, told AFP.
The ferry was carrying 43 people, 17 of whom were rescued.
The search was continuing for the other missing persons, he said.
Frequent dramas
Accidents at sea are numerous in Indonesia, an archipelago made up of 17,000 islands, and where safety instructions are not always respected.
Just last week, a ferry carrying more than 800 people ran aground in East Nusa Tenggara province and was stranded for two days.
No one was hurt.
In 2018, more than 150 people drowned when a ferry sank in Sumatra, on one of the deepest lakes in the world.
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