Mudslides killed more than 200 people after heavy rains caused rivers to overflow in Colombia's Putumayo province, authorities said.

Gabriel Umana, a spokesman for the Colombian Red Cross, told CNN on Saturday 234 people have died and 220 are missing.

He said at least 202 people were injured and 300 families displaced. Twenty-five houses were destroyed.

President Juan Manuel Santos said it was impossible to predict the number of deaths.

"Unfortunately, it is possible that the number of deaths will go up because we have a lot of missing people," Santos told TV channel Cable Noticias.

"We don't know yet where they are. Many people are coming to us saying, 'My son is missing, my father is missing, my mother is missing'. We are working on putting a list for the total number of people missing."

Santos said 130 mm of rain fell in the area on a single night on Friday, setting off the deadly torrents, CNN reported.

The monthly average is about 400 mm, he said.

The President has declared a state of emergency.

Three rivers in the area, including the Mocoa and San Boyaco, overflowed and unleashed muddy waves into homes, over cars and onto bridges.