The man picked up several saws in the store's saw section and managed to cut both arms down to the bone before police arrived on scene, according to the grisly report.
One of the saws was intended for cutting sheet rock.
The gruesome incident took place at a West Covina, Calif., Home Depot location.
Art Hurtado, an off-duty fire chief from Pasadena, was shopping at the store at the time and rushed to help when he saw what was happening. Police had found the man unresponsive in the store aisles, bleeding severely, and Hurtado told NBC News " the whole store is in chaos."
Hurtado asked for towels and cut sections of nylon rope to make tourniquets that helped control the man's bleeding, with assistance from police and Home Depot workers.
A police corporal said Hurtado can be credited with saving the man's life.
"It was a godsend," Cpl. Rudy Lopez, with West Covina Police Department, told NBC News. "He happened to be at the right place at the right time, probably saved his life."
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