(PORT HURON) -- An Oregon woman accused of dumping the body of her 89-year-old mother behind a Michigan thrift store has been charged with murder. New charges against Kelly Rhodes of Salem, Oregon, were disclosed Wednesday when she appeared in court on a charge of moving the body of 89-year old Mary Gertrude Grenia. The body was covered with a blanket behind a Goodwill Industries store in Port Huron Township and found in March. 49-year-old Rhodes was charged with open murder and abuse of a vulnerable adult. Open murder means a jury can determine if it's first or second-degree murder. The new charges came after prosecutors received an autopsy report Tuesday. Rhodes remains jailed without bond. Her preliminary exam is set for Tuesday, June 25.