GERONIMO, Okla. (AP) - The lack of any sighting in Oklahoma of a missing 7-year-old girl has prompted some officials to argue that missing-children alerts shouldn't be limited just to the state where a child disappeared.

Comanche County Sheriff Kenny Stradley said he had assumed Amber Alerts were broadcast nationwide, but found out otherwise during last week's search for Aja Johnson (shown) after the little girl's mother, Tonya Hobbs, was found slain. An Amber Alert for Aja said she was believed to be in the company of her stepfather, Lester Hobbs.

Oklahoma State Bureau of Investigation spokeswoman Jessica Brown said Lester Hobbs (shown) got a 24-hour start before his wife's body was found and had plenty of time to travel far from Oklahoma. She said that's why a national Amber Alert system is needed.