CALGARY, Alberta (AP) — Three more horses competing in the Calgary Stampede have died, bringing to six the number of deaths at the annual rodeo and exhibition.

The horses were injured during chuck wagon races and were euthanized.

Stampede officials say on their website that the horses went down Sunday night in the eighth race. A horse on the wagon driven by Evan Salmond broke a bone in a hind leg. Two others in the same team were also hurt, forcing all three to be euthanized.

Stampede authorities plan to review the chuck wagon races, saying safety is "paramount to our values and brand integrity."