Olympic-winning horse dies

Canada is down one Olympics-winning horse after it died Sunday. 

His name was Hickstead. He helped Eric Lamaze win in the 2008 Olympics. Hickstead died during a World Cup event when he collapsed to the ground. 

Lamaze says it looked like a heart attack. But the International Equestrian Federation says the cause of death is unknown.

The competition was cut short and there was a minute of silence. Hickstead made over three million dollars during his career.