Footage has emerged showing the three-storey wooden stand filled with spectators falling at a stadium in El Espinal, Tolima department.
The traditional "corraleja" event involved members of the public entering the ring to engage the bulls.
President-elect Gustavo Petro urged local officials to ban such events.
"I ask mayors not to allow more events involving the death of people or animals," he said.
It was not the first time such an accident had happened, he added.
