On this day, Dec. 6, in 1868, a guard shot during a robbery died from gunshot wounds, sparking a vigilante hanging of three Reno Brothers in Indiana.

The Reno Brothers are credited with the first train robberies in post-Civil War America, setting off a wave of similar holdups throughout the Old West.

After the guard died from wounds he suffered at the hands of the gang several months earlier, dozens of men in scarlet masks traveled by train on Dec. 11 to the Floyd County Jail, where Frank Reno, the gang's leader, and his brothers, William and Simeon, were being held.

In the early-morning hours of Dec. 12, the vigilantes shot the sheriff, grabbed his keys and hung the brothers dead.

This is believed to be the only time in U.S. history that a federal prisoner had been lynched by a mob before trial.

- Scott McCabe