A huge explosion at a gasoline and diesel pipeline in Colombia killed 11 people, injured nearly 100, and destroyed dozens of homes on Friday, in an accident described by President Juan Manuel Santos as a great tragedy.

The explosion at a pipeline controlled by Colombia's state-owned Ecopetrol was caused by a landslide following heavy rains, the company said, retracting an earlier statement that fuel thieves were probably to blame.

This really is a great tragedy ... For the time being there are 11 people dead, 78 injured, of which about nine or ten are in critical condition, Santos said during a visit to the village of Dosquebradas in the western region of Risaralda.

Many children were among the injured, he added, speaking amid blackened houses while firefighters searched for survivors among the debris.

Ecopetrol said there were several explosions and a fire. As a result of severe winter weather in the country there was a landslide, which put pressure on the pipeline and it broke ... leading to a spill of fuel in the river, the company said.

In its statement late on Friday, Ecopetrol said the number of injured had increased to 99 people.

The pipeline is about 140 miles (230 kms) long and links Salgar, in the centre of the country, to western regions. Ecopetrol said the supply of fuel should not suffer because there are two other pipelines pumping fuel to western provinces.

Locals told Reuters that they were awakened by a strong gasoline odour in the wee hours of Friday and could not breathe properly, which prompted many to go outdoors.

We were gasping for air, and were able to come out, but there were other people who could not leave before the flames and the explosions started, said Hugo Nelson Sanchez, 36, whose house was destroyed.

Colombia has endured months of heavy rains, triggered by the La Nina weather phenomena, in which dozens of people were killed and bridges, roads and other key infrastructure were destroyed, causing billions of dollars in damage.

(Additional reporting by Luis Jaime Acosta; Writing By Eduardo Garcia; Editing by Gary Hill)