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New York Daily News
The 37-year-old Tanner, who held the UFC middleweight title in 2005, last fought in June at the Ultimate Fighter finale.
Tanner wrote on his blog last month, "I'm hoping that very soon I'll be sitting out in the quiet of the desert beneath a deep blue midnight sky, listening to the calm desert breeze. ... I want to go to these places, the quiet, timeless, ageless places, and sit, letting silence and solitude be my teachers."
UPDATE: UFC Mourns Former Champ Evan Tanner, Dead at 37, Cause of Death Unknown.