CHICAGO, (AP) -- French officials are refusing to extradite an American suspected of killing a dermatologist last year because he recently became a French citizen, prosecutors said. Hans Peterson, 29, turned himself in to French authorities Aug. 6 on the Caribbean island of St. Martin after an arrest warrant was issued for him in Chicago. He is accused of fatally stabbing Dr. David Cornbleet in the dermatologist's downtown Chicago office in October. Peterson, a U.S. citizen whose mother is French, obtained French citizenship in May while living on St. Martin, the Chicago Tribune reported. Peterson is being held in French-controlled...