HONG KONG — Rescuers in Indonesia were searching on Wednesday for more than 160 people who were missing after a ferry sank in a lake during a major holiday, officials said.

Indonesia’s National Disaster Management Agency said Wednesday on Twitter that 166 people were still missing from the sinking late Monday afternoon in Lake Toba, a popular sightseeing spot on Sumatra Island. Eighteen people had been rescued and one body had been recovered, the agency said.

Indonesia is the world’s most populous Muslim-majority nation, and the accident occurred during Eid al-Fitr, the Muslim holiday that marks the end of the holy month of Ramadan. Millions of Indonesians have been traveling home to celebrate the holiday, known there as Idul Fitri.