A speedboat carrying 93 Indonesian migrant workers from Malaysia sank off Batam Island on Wednesday, killing 17 of them, Indonesia's national disaster agency said.
The boat set sail from the southern Malaysian state of Johor and was headed towards Indonesia's Batam island, just south of Singapore, the Indonesian national disaster mitigation agency said in a statement.
A police spokesman said earlier at least 18 people were killed.
The boat crashed into a reef after being hit by big waves and strong wind, and sank at around dawn, the disaster agency said.
About 39 people were evacuated and a search and rescue team was looking for the rest.
Many Indonesians work in Malaysian factories and plantations.