It was believed to be carrying more than 250 people.
Some passengers are reported to have been rescued after being spotted by fishermen, but it isn't clear how many were found.
The ship capsized and went down in stormy weather.
A search operation is under way after a ferry carrying about 250 passengers and 17 crew sank in stormy seas in central Indonesia, officials say.
A search operation is under way after a ferry carrying about 250 passengers and 17 crew sank in stormy seas in central Indonesia, officials say.
At least 100 people are feared dead after the ferry sank off the coast of the Indonesian island of Sulawesi.
The ferry was sailing from Pare-Pare, in South Sulawesi, to Samarinda, in East Kalimantan, when it was battered by four-metre waves.
About 150 people were rescued but the rough seas are hampering further efforts.
The captain of the Teratai Prima, who was among those pulled alive from the sea, said that about 150 people managed to jump off before the ferry went down.
A few survivors are said to have been spotted by fishermen as they drifted on lifeboats, the BBC's reports.
Indonesia relies heavily on ferry services to connect the main islands in the archipelago, the world's largest. But accidents are common, largely due to years of under-investment in infrastructure and a tendency to overload ferries.
More than 400 people died when a ferry sank in 2006.
