Jeremy McDiarmid reports: "A cascade of earth and rock"

At least a dozen more were missing and feared dead after Thursday's slides 240km west of the capital Bogota, said Monica Yamhure, the federal director for disaster response.

The first landslide buried a group of houses on the outskirts of the town of Argelia at dawn on Thursday morning.

A second much larger landslide hit the rescue operation trying to free victims of the first.

Victims of the later disaster, many thought to be Red Cross workers and firefighters, were buried alive while digging to reach survivors entombed under tons of earth and rock.

Around 40 people were believed to be directly in the path of the second landslide.

Hope fades

Workers laboured frantically to try to free the buried, and some were pulled out.

But as darkness fell, Colombian Red Cross officials said they had little hope of finding any remaining survivors.

Rescue operations involving 200 people were suspended late on Thursday night because of the risk of another mudslide, said Ms Yamhure.

Argelia, home to 8,000 people, is in the coffee-growing region that was struck in January by a devastating earthquake that killed over 1,100 people.

La Niña blamed

Unusually heavy rains over the past few weeks have forced rivers to break their banks and caused a series of smaller landslides in Colombia.

Meteorologists blame the prolonged storms on the La Niña weather phenomenon, caused by cooling currents in the Pacific Ocean.

"The rainy season here is just horrible. We've been really hit hard," said municipal spokeswoman Amparo Lopez.