At least 23 children were killed and about 30 injured in the Colombian capital Bogota on Wednesday when a construction vehicle slid off a mountain road and crashed onto a school bus on a highway below, police said.
The victims, some as young as five, were going home when the 40-ton truck fell at least 13 feet (four meters) and crushed their bus.
Authorities said 36 people were injured. At least three of them were adults - the drivers of the two vehicles and a teacher on the bus - and the rest were thought to be children.
Bogota Mayor Luis Eduardo Garzon ordered an investigation to determine why the truck, which had been digging up asphalt, veered off the mountain pass.
"There aren't words. What's happened here is profoundly painful," Garzon said.