Ex-Cowboys RB Marion Barber III died of heat stroke

Authorities say heat stroke is to blame for the death of former Dallas Cowboys running back Marion Barber III.

The Collin County medical examiner's office said the 38-year-old's death has been ruled an accident.

Police were performing a welfare check when they found Barber dead in his apartment in Frisco, Texas, on June 1.

A fourth-round pick by Dallas in 2005, Barber made the Pro Bowl in 2007. He rushed for 4,780 yard