A bull attacked several people after the collapse at the Gilberto Charry Bullring in the municipality of Espinal, according to officials.
A number of children were reported missing in the chaos following the event.
Many of the injured were transferred to the nearby San Rafael Hospital, which has become inundated with patients, though other local hospitals have sent ambulances to transfer some of the wounded.
"We will request an investigation into the events. (We wish) a speedy recovery for the injured and (send our) solidarity to the families of the victims," Colombian President Ivan Duque tweeted, Xinhua reported.
President-elect Gustavo Petro urged Colombian mayors not to authorize any event related to the death of animals, such as bullfighting.
