In this Saturday, February 22, 2014 photograph, members of India's Dongria tribe watch animal sacrifice during the two-day long Niyamraja Festival atop the Niyamgiri hills near Lanjigarh in Kalahandi district, Orissa state, India. Every year, members of this indigenous group celebrate this festival sacrificing animals and birds in worship of their deity. (Photo by Biswaranjan Rout/AP Photo)

Members of Dongria tribe watch animal sacrifice during the two-day long Niyamraja Festival atop the Niyamgiri hills near Lanjigarh in Kalahandi district, Orissa state. (Photo by Biswaranjan Rout/AP Photo)

A member of Dongria tribe girl faints after dancing in trance during the two-day long Niyamraja Festival atop of the Niyamgiri hills near Lanjigarh in Kalahandi district, Orissa state. (Photo by Biswaranjan Rout/AP Photo)

A Dongria tribe girl holds her traditional weapon and dance on the last day of their two days long Niyamraja Festival atop of the Niyamgiri hills near Lanjigarh in Kalahandi district, Orissa state. (Photo by Biswaranjan Rout/AP Photo)

Members of Dongria tribe holding their traditional weapons rush to sacrifice a buffalo during the two-day long Niyamraja Festival atop the Niyamgiri hills near Lanjigarh in Kalahandi district, Orissa state. (Photo by Biswaranjan Rout/AP Photo)

Members of Dongria tribe sacrifice a buffalo during the two-day long Niyamraja Festival atop the Niyamgiri hills near Lanjigarh in Kalahandi district, Orissa state. (Photo by Biswaranjan Rout/AP Photo)

Female members of Dongria tribe warm themselves near a fire during the two-day long Niyamraja Festival atop the Niyamgiri hills near Lanjigarh in Kalahandi district, Orissa state. (Photo by Biswaranjan Rout/AP Photo)

During the dancing in trance at the Niyamraja Festival many female participants faint due to exhaustion. (Photo by Biswaranjan Rout/AP Photo)

Every year, members of Dongria tribe celebrate the Niyamraja festival sacrificing animals and birds in worship of their deity. (Photo by Biswaranjan Rout/AP Photo)

A woman carries a pig for sacrifice as members of Dongria tribe arrive for the two-day long Niyamraja Festival atop the Niyamgiri hills near Lanjigarh in Kalahandi district, Orissa state. (Photo by Biswaranjan Rout/AP Photo)

A member of Indiaís Dongria tribe wearing traditional ornaments watches others dance during the two-day long Niyamraja Festival atop of the Niyamgiri hills near Lanjigarh in Kalahandi district, Orissa state. (Photo by Biswaranjan Rout/AP Photo)

A member of Dongria tribe wearing traditional ornaments dances during the two-day long Niyamraja Festival atop of the Niyamgiri hills near Lanjigarh in Kalahandi district, Orissa state. (Photo by Biswaranjan Rout/AP Photo)

Women of Dongria tribe carry firewood as they arrive for the two-day long Niyamraja Festival atop the Niyamgiri hills near Lanjigarh in Kalahandi district, Orissa state. (Photo by Biswaranjan Rout/AP Photo)