A tourist ferry sank into the waters of the Indonesian island of Sumatra, in Lake Toba, one of the deepest lakes in the world.
The authorities expressed concern that many people could be trapped inside the ferry.
The wooden ferry was not authorized to carry more than 60 people, and you had a passenger list, but 18 people were recovered and 190 were still missing.
"We have coordinates since the time the ferry sank, but we need to check," said Boud Iwan, director of the national search and rescue agency in Medan, capital of Sumatra province.
"We are now looking for 190 people," he said, after relatives and friends of victims reported more missing.
A team of 25 submarines, including naval personnel, are searching for the ferry, as well as underwater vehicles, but can not operate at a depth of more than 380 meters, Boud Iwan said.
Dozens of grieving families are waiting for new news from the information center set up on the lake shore.
Lake Toba, 450 miles long, is located on a giant volcano that erupted 75,000 years ago in one of the world's biggest volcanic eruptions.