The correct answer is "hostilities between American Indians and the Colorado militia."
The Wounded Knee Massacre, which occurred in 1890, was a confrontation between Native Americans who belonged to the Minincojou and the Hunkpapa Lakotas and the Colorado Militia, led by Colonel James Forsyth.
As a result of this battle, nearly 300 Native Americans and 25 American soldiers died. In 1990, the US Congress passed a resolution expressing a "deep regret" for the massacre.
