US police have arrested a man in the 1988 slaying of an eight-year-old girl.

Authorities say John Miller, of Indiana, agreed to speak with police in Fort Wayne, in the midwestern US state, and made incriminating statements about abducting, assaulting and killing April Tinsley.

An affidavit released by the Allen County prosecutor says investigators have DNA evidence linking Miller to the girl.

A recent search of Miller's rubbish helped police make a DNA match.

Charges could be formally filed this week. It wasn't immediately known if Miller has a lawyer who could comment on the arrest.

April's body was found in a ditch, about 30km from her Fort Wayne neighbourhood, three days after she disappeared in April 1988.

Two years after the killing, the words "I kill 8 year old April M Tinsley did you find her other shoe haha I will kill agin" were found scrawled on a barn in the area, reports the News-Sentinel.

April's family left Fort Wayne in 1991 but returned five years ago.