French gymnast Samir Ait Said has broken his leg while performing in the vault event at the Rio Olympics.

His left leg was left dangling from below the knee after it snapped when he landed awkwardly on the mat.

Horrified audience members watched the 26-year-old, who has won gold and silver on the rings in past competitions, as he squirmed in agony on the mat after his injury.

Medics rushed to help the young gymnast, and he was taken out by stretcher.