Floods and landslides killed 16 people and left at least two missing in Indonesia's North Sulawesi province, an official said on Thursday.
Floods triggered by days of heavy rain have hit six districts and towns in the province this week and displaced more than 40,000 people, said Noldy Liow, the head of the local disaster management agency.
An unknown number of people were believed missing after a hill caved in and the mud slammed into motorists in the town of Tomohon on Wednesday, Liow said.
"Witnesses said cars and motorcycles were thrown into a 50-metre deep ravine when the landslide hit them," Liow said.
"They were trapped in a traffic jam because of flooding when the incident happened."
The provincial capital Manado and the neighbouring town of Tomohon were the worst hit, he said.
Floods and landslides are common during the rainy season in Indonesia.
At least four people were killed this week as floods hit parts of the Indonesian capital, Jakarta.