The trial of a 76-year-old pawn shop owner charged with killing a woman in 1998 is underway in Aroostook County. Prosecutors contend that George Jaime Sr. of Presque Isle killed 38-year-old Starlett ‘‘Star’’ Vining by stabbing her and beating her. The defense said there is no evidence Jaime did that because Vining’s body was never found. WAGM-TV reported Assistant Attorney General Andrew Benson told jurors Tuesday that details of the death came from Jaime’s son, who said he helped clean up afterward. Jaime’s been held without bail since his arrest last year.