Children were among those killed in the incident, which took place in a remote area some 200 km from the city of Sucre, the poor Andean nation's constitutional capital.

"We have policemen, people from the provincial government and the army helping with the search and rescue mission but the area is too large," Police Chief Ivan Marquez told the ABI state news agency.

Marquez said the incident happened on Friday, but the remote location meant the details took days to come to light. At least 19 people were also hurt, he said.

Survivors told local media how they grabbed onto rocks and plants to stop themselves being pulled into the water as the vehicles crossed the flooded Mollepunku river.

Floods frequently cause devastation in Bolivia during January, the height of the rainy season. Leftist Bolivian President Evo Morales has blamed extreme weather on pollution from wealthy nations.

Reuters