EDMOND, Oklahoma -- One medical expert believes it was a blood clot or embolism that killed a 16-year-old Edmond North football player this week.

Ryan Smith broke his leg during practice Tuesday, October 11,  and died the next day. The State Medical Examiner hasn't given an official cause of death yet.

An associate professor of orthopedic surgery at the University of California-Los Angeles said a fat embolism or blood clot can be caused by a severe broken bone, and could have contributed to Smith's death.