CHEYENNE, Wyo. (AP) — Authorities say a 52-year-old man has died after falling down a well shaft at a southeast Wyoming dairy farm where he succumbed to methane fumes from cow manure and drowned in a pool of water.

The Laramie County Sheriff's Office identified the victim as Erasmo B. Gonzalez, who lived on the farm in the small community of Carpenter.

Three others who tried to save Gonzalez Tuesday were treated for methane exposure. Two were hospitalized.

Sheriff's spokesman Lt. Don Hollingshead says Gonzalez slipped and fell down a 10- to 12-foot (3- to 3.6-meter) well shaft where he lost consciousness because of methane fumes that had seeped into the well shaft in water that drained off farm manure piles. Gonzalez drowned in the well.

The Occupational Safety and Health Administration is investigating.