CINCINNATI -- Authorities are searching a 1-acre section of a Cincinnati-area landfill for clues to the disappearance of an elderly Ohio couple.

Officials say the couple's car was last seen Wednesday parked near an Interstate 75 rest area, about 100 miles southwest of their Bellefontaine home.

Trash from the rest area was dumped at the Rumpke landfill, but Bellefontaine police say they're not certain the landfill contains anything connected to the case.

Eighty-four-year-old Richard Russell and 85-year-old Gladis Russell have been missing since Wednesday, the day a woman was found dead in a home the Russells sold to Sam Littleton.

Littleton also was last seen Wednesday and has been charged in absentia in the death of 26-year-old Tiffany Brown, his girlfriend's daughter. Police found his truck a short distance from the Russells' home.