Charles Willden heard the emigrants threaten violence against Utah residents and some claimed to have been participants in Joseph and Hyrum Smith's murder on the very day of the massacre.
Charles Willden, Affidavit, Beaver county, Utah, February 18, 1882, as found in the Collected material concerning the Mountain Meadows Massacre, 1859-1961, MS 2674, Church History Library
. . . about the 11th day of September of said year 1857, I saw a company of Emigrants . . . Said Company halted near the Great Mill . . . Return from the Mill, and between the Latter and the distillery I heard some fifteen to twenty men of said company talking in a loud excited and boisterous manner profaning and threatening to do bodily harm and kill some of the citizens of said Lower Town saying and affirming that they had helped to kill Joseph Smith at Carthage . . .