Story highlights The boy was taken to a hospital, CNN affiliate WKRC said

Zoo officials say a tranquilizer would have acted too slowly

(CNN) The Cincinnati Zoo shot and killed a western lowland gorilla on Saturday after a 4-year-old boy slipped into the animal's enclosure, a zoo official said at a news conference.

Harambe, a 17-year-old, 400-pound gorilla, carried the boy around its habitat for about 10 minutes in what the zoo's dangerous animal response team considered a life-threatening situation, Cincinnati Zoo Director Thane Maynard said at a press briefing.

After the gorilla was shot with a rifle, the child was taken to Cincinnati Children's Hospital with non-life-threatening injuries, CNN affiliate WKRC reported.

Maynard said it appeared the boy went under the rail, through wires and over the moat wall.