By Yudi Saputra
PEMATANG SIANTAR, Indonesia (Reuters) - Indonesian rescue workers fought heavy rains and two-meter waves on Tuesday in a search for survivors after a ferry with at least 80 passengers on board sank in Lake Toba, a popular tourist destination in North Sumatra.
An estimated 18 people had been rescued and one passenger was confirmed dead after the ferry sank on Monday. Some 100 rescue personnel, including military and police officials, were deployed in the search.
It was not immediately clear if foreigners were among the missing passengers.
"Our joint teams moved out at 7 am," said Budiawan, head of the search and rescue agency in the nearby city of Medan, adding that the teams would work for as long as the weather allowed.
"It might take time to find victims who drowned," he said, adding that some bodies may be trapped inside the sunken vessel.
The wooden ferry had a capacity of 60 passengers but may have been carrying 80 people and dozens of motorcycles on Monday, said Sri Hardianto, an official at Indonesia's transport ministry.
The National Disaster Mitigation Agency said there were unconfirmed reports of up to 130 people on board the ferry, which was hit by high waves and strong winds.
Video footage provided by the agency showed people on another ferry throwing life preservers and life jackets to several people in the water on Monday evening.
On Tuesday, distressed relatives of missing passengers held each other and cried as they waited for news at Tigaras Port, according to pictures from the scene.
Ferry accidents are common in Indonesia, a vast archipelago, especially during the Islamic holiday of Eid when millions of people make the annual journey by land, sea and air to their hometowns after the holy fasting month of Ramadan.
A longboat carrying around 43 people sank off Makassar on Sulawesi island last week, killing 13, and a speedboat carrying 30 passengers sank off South Sumatra, killing at least two.
Lake Toba, a popular tourist destination, fills the caldera of a giant dormant volcano and is one of the deepest lakes in the world.