On April 20, 1914, gunfire broke out between strikers and the Colorado National Guard. The troops initially positioned themselves on Water Tank hill and used a machine gun to strafe the colony. They set up a second machine gun across the railroad tracks west of the colony. The gunfire lasted from breakfast into the evening. Strikers took arms and retreated from the colony to draw fire from their families. The National Guard finished the massacre by torching the strikers' tents. At the end of the massacre, 20 strikers died and the rest of the Ludlow strikers were left homeless.  

Following the Ludlow Massacre, the National Guard took control of the ruins of the Ludlow colony. They denied access to outsiders and the strikers immediately following the massacre. In this photograph, troopers pose in defensive positions in the Ludlow ruins. This pose is most likely for the photographer and not for any real threat.