A new report says two teenagers who hanged themselves at a youth detention center in East Tennessee had shown a history of suicidal behavior. The Tennessee Commission on Children and Youth released its report yesterday. The Knoxville News Sentinel reports 16-year-old Brandon Greene of Mountain City, Tennessee, hanged himself July 13, and 18-year-old Frank Cass of White County, Tennessee, hanged himself Aug. 1. The commission said employing more guards at Mountain View Youth Development Center would have provided a better watch on the inmates and might have helped prevent their deaths. The suicides were the first at the center in 20 years.