Police said in a statement that 18 people were rescued and one body was recovered, unchanged from figures released by disaster and police officials almost a day earlier on Monday evening.
"Many people have reported their relatives missing", Budiawan, head of the search and rescue agency based in the nearby city of Medan, told Reuters after a coordination meeting.
The 1,145-square kilometer (440-square mile) lake, formed out of an ancient super volcano, is a popular sightseeing destination.
The wooden vessel sank Monday afternoon with an estimated 80 people aboard, authorities have said, just days after more than a dozen people were killed in another maritime accident across the country.
Authorities believe the craft was operating illegally with no manifest and the passengers had not been given tickets. Distraught relatives have gathered at major ferry docks on the lake, hoping for news of missing family members.
Spokesperson of the National Disaster Mitigation Agency of Indonesia Sutopo Purwo Nugroho said that the KM Sinar Bangun boat sank at about 5:30 p.m.as it sailed from Samosir, a volcanic island in the middle of Lake Toba to Parapat town.
As you know, the boat capsized on lake Toba in North Sumatra on Monday evening, June 18.
"I was desperate, I was scared to death".
Jakarta, Jun 19 (Prensa Latina) At least one person died and another 128 disappeared when a ferry sank due to bad weather conditions in Lake Toba, Indonesia, official sources reported today. "I'm afraid my family is dead", she said, weeping.
Maher Tamba, an official with the local disaster agency, said at least half a dozen vessels had searched for survivors since Monday night.
Ferry accidents are common in Indonesia, a vast archipelago, especially during the Islamic holiday of Eid al-Fitr, which fell last week, when millions of people travel by land, sea and air to their hometowns after the fasting month of Ramadan.