FRISCO, Texas -- Former Dallas Cowboys and Chicago Bears running back Marion Barber III has died at the age of 38, the Cowboys said in a statement Wednesday.

"We are heartbroken by the tragic death of Marion Barber III," the team said. "Marion was an old-school, hard-nosed football player who ran with the will to win every down. He had a passion for the game and love for his coaches and teammates. Our hearts go out to Marion's family and friends during this difficult time."

The cause of Barber's death is unknown.

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Police in Frisco, Texas, said in a statement that they responded to a welfare concern Wednesday at an apartment they believed to be leased by Barber. Police said they were investigating an unattended death at the location but didn't identify the individual in their statement.

"The NFL mourns the tragic loss of Marion Barber III and we extend our deepest condolences to his family and loved ones," the league said in a statement.

Barber was drafted by Dallas in the fourth round of the 2005 NFL draft out of Minnesota. He was named to the Pro Bowl in 2007 despite not starting a game for a 13-3 team that finished with the best record in the NFC. He led the Cowboys with 975 yards rushing and 10 touchdowns that season.

After he was released by the Cowboys following the 2010 season, he spent one year with the Bears. He finished his career with 4,780 yards and 53 touchdowns on 1,156 carries in 99 games. He also caught 179 passes for 1,330 yards and six touchdowns.

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Sometimes images are the best way to honor the figures we've lost. When tragedy swiftly reminds us that sports are far from the most consequential thing in life, we can still look back on an athlete's winning moment that felt larger than life, remaining grateful for their sacrifice on the court and bringing joy to millions.

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