Revolutionary leader General Pancho Villa attacked the town of San Andrés, and the battle concluded when the American soldier of fortune charged the federal positions and routed the enemy.

A thousand government soldiers were killed, and 400 prisoners were executed by Villa's self styled executioner, Rodolfo Fierro.

In next day on the 27th, Villa ordered his machine gun detachments under the command of the American soldier of fortune, Major E.L Holmdahl.

Holmdahl was wounded, but the cavalry reached the federal positions and quickly overran the trenches and routed the enemy from the field.

The federals had lost with 1,000 dead and 400 captured, as well as losing more than fifty artillery pieces, 400 Mauser rifles, 20,000 rounds of ammunition and seven railroad trains loaded with food, medical supplies, and uniforms.

[4] Martín Luis Guzmán, a Mexican Journalist, novelist, and historian credited Holmdahl with winning the battle.