On Dec. 29, 1890, Chief Big Foot's Minneconjou and Hunkpapa Sioux band, including 108 warriors and 250 women and children, was encamped at Wounded Knee under guard after surrendering the previous day to the U.S. 7th Cavalry. The crisis grew out of unrest on the Pine Ridge Reservation, reductions in beef rations, and the spread of Ghost Dancing, encouraged by leaders including Sitting Bull, Hump, Big Foot, Kicking Bear, and Short Bull, who told Sioux warriors that Ghost Shirts would protect them from bullets and help restore the old buffalo days. After Indian Agent Royer called for troops on Nov. 15, 1890, several thousand U.S. Regulars assembled in Dakota Territory, and after Sitting Bull was killed on Dec. 15, some of his followers joined Big Foot's band. On the morning of Dec. 29, reinforcements reached Wounded Knee, Col. Forsythe commanded 470 men, four Hotchkiss guns were placed on a hill west of the camp, and the band was encircled while Big Foot, sick with pneumonia, lay in a warmed tent beneath a white flag. The Sioux were ordered to surrender their weapons before going to Pine Ridge, and while Capt. Wallace's detail searched the tipis, Yellow Bird moved among the warriors with an eaglebone whistle, urging resistance and declaring that Ghost Shirts would protect them. A shot was fired, the troops unleashed a deadly volley into the council warriors, and a bloody hand-to-hand struggle followed in which the mostly lightly armed Sioux faced soldiers and Hotchkiss guns firing explosive shells indiscriminately into groups of warriors, women, children, and even their own disarming soldiers. Surviving Indians fled toward a dry draw and along Wounded Knee Creek, but pursuit by the 7th Cavalry killed more men, women, and children. Within an hour, 146 Indians, women, and children lay dead in the valley, with bodies scattered for two miles; 20 soldiers were killed on the field and 16 later died of wounds. The wounded were taken to Pine Ridge Agency, a blizzard followed, and four days later Army personnel buried the Indian dead in a common grave. The encounter ended Ghost Dancing and became known as the Wounded Knee Massacre, the last armed conflict between the Sioux Indians and the United States Army.