Authorities say there are no signs of foul play in the disappearance of a Nebraska woman and her 11-year-old son.

Plattsmouth police say Charlotte and Owen Schilling were last seen about 10 a.m. Thursday in the Plattsmouth area, when she checked the boy out of elementary school. They haven't responded to cell phone calls from relatives.

Police say Charlotte Schilling's vehicle was found Friday near Lake Manawa, which is just across the Nebraska border near Council Bluffs, Iowa. Her wallet and cell phone were in the car.

Officer John Hardy said there is concern about the whereabouts of Charlotte and Owen Schilling but the investigation hasn't shown evidence of a crime.