September 11.....1857
The Church of Jesus Christ of Latter-day Saints (LDS Church) denied any involvement by Mormons, and was relatively silent on the issue. In 1872, however, it excommunicated some of the participants for their role in the massacre. Since then, the LDS Church has consistently condemned the massacre, though acknowledging involvement by local Mormon leaders. In September 2007, the LDS Church published an article in its official publications marking 150 years since the tragedy occurred.*
*Richard E. Turley Jr., The Mountain Meadows Massacre, lds.org, 2007-08-29
Weird.