Police said they still don't know the woman's identity, or whether she was killed in 1997 or 1998.
"If any identification is made, it will have to be by dental records," Johnson said.
Police are investigating missing persons reports and checking anyone who could be a potential victim, said Hagerstown Police Chief Dale Jones.
A Conrail employee found the body in a wooded area on the west side of the 900 block of South Burhans Boulevard.
Miller, 19, is described as a white woman, 5 feet 4 inches tall, 125 pounds, with brown hair and blue eyes.
Police described the body found Monday as that of a white woman in her late teens or early 20s, between 5 feet 2 and 5 feet 5 inches tall. She had medium to light brown hair, a gap between her front teeth and was wearing an extra-large, black, Fruit of the Loom short-sleeve shirt with a "New Orleans Bourbon Street" logo.
She also was wearing a dark green bra, short blue jeans and black shoes.
Miller is wanted on two counts of accessory after the fact, felony theft, auto theft and unauthorized use of a motor vehicle.
She is believed to have been with a man who had been accused in the fatal beating of Darrius Allen Fetterhoff, 58, of Grant Street, Greencastle, Pa. Fetterhoff died Aug. 28, 1997.