At least 20 people are missing in Colombia after a mudslide swept over people changing from one bus to another because an earlier slide was blocking a mountain road.

The accident happened in the north-west of the country, on the road between the towns of Giraldo and Canasgordas, 200 miles from the capital, Bogota.

Officials said passengers got off one bus and were crossing the blocked portion of the road to board a second bus that had been sent to pick them up because of the earlier landslide when another mudslide cascaded down the mountain.

The slide also destroyed four or five homes, they said.

About 100 workers began digging looking for the missing but the effort had to be suspended because of dangerous conditions caused by rain and poor visibility, according to officials.

Authorities have reported that the strong rainy season caused flooding and made many roads unusable across Colombia in recent weeks.