SIOUX FALLS, S.D. (AP) - Six people accused of stealing identities in South Dakota and using them to fraudulently collect tax refunds have pleaded not guilty in federal court in South Dakota.

Four of the six are former University of South Dakota football players. One of them - 21-year-old Alphonso Valdez - is accused by the Internal Revenue Service of being the leader of the fraud scheme.

Nine people from South Dakota and Florida are charged in the alleged plot. They were indicted last month. Authorities say the IRS paid fraudulent claims of about $500,000 before the scheme was uncovered.

Two others pleaded not guilty last month, including 21-year-old Christopher Lundy, who was still on the team this past fall, and former USD track athlete and student body president Terry Liggins.

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