A resident called police on Friday night after spotting Anthony Dewayne Ware, 35, sitting on the front porch of a home with a gun, police said.
When officers arrived, Ware bolted and fled into the nearby woods, CNN quoted Tuscaloosa police assistant chief Ronnie Dunn as saying.
When the officers caught up with him, he resisted arrest, Dunn said.
Police pepper-sprayed Ware, who continued struggling but was eventually handcuffed. But while officers were walking out of the woods with him, the man collapsed.