A Palmer resident has been sentenced to 50 years in federal prison on multiple charges of child sexual exploitation. Forty nine year old Robert Earl Cunningham, also known as “Bear” Cunningham and a registered sex offender, will serve the term concurrently with an 88-year state sentence.Download AudioCunningham was sentenced in Anchorage Tuesday by U.S. District Court Judge Sharon Gleason, to the maximum terms allowed on six counts of child sexual exploitation. The terms are 50 years on two of the counts and 30 years on four of the counts. The sentences are to run concurrently to each other, and to the state sentence.Assistant U.S. Attorney Audrey J. Renschen, who declined to go on tape, says the state had already sentenced Cunningham on multiple charges of sexual abuse of a minor. According to an Alaska State Trooper dispatch, Cunningham was sentenced in September of this year under a plea agreement to the 88-year state sentence. Renschen says the federal charges stem from the use of materials shipped across state lines to produce child pornography.