Gabby Giffords: US Can't Settle Disputes With Violence

Former U.S. Rep. Gabrielle Giffords, who suffered a serious brain injury in a 2011 shooting in Arizona, said she was "horrified" to hear Charlie Kirk's was shot and killed during his speaking event at Utah Valley University in Orem, Utah.

"Democratic societies will always have political disagreements, but we must never allow America to become a country that confronts those disagreements with violence," she said on social media.