'He's dragging my son! I can't watch this' - 911 recording of Cincinnati Zoo mother released

Emergency service recordings have revealed the confusion and panic after a three-year-old boy plunged into Cincinnati Zoo's gorilla exhibit and was picked up by one of the animals.

During the 911 recordings of Saturday's incident, which ended when the 17-year-old western lowland gorilla called Harambe was shot dead by zoo staff, the boy's mother is heard pleading for help while repeatedly shouting at her son: "Be calm!"