CINCINNATI (AP) — Investigators believe a man used a tool to beat his 5-year-old niece to death in Ohio, a sheriff said Tuesday.

Authorities found the tool at the home east of Cincinnati where Jada Beth Williams' body was found, Highland County Sheriff Ron Ward said. Preliminary autopsy results found that the girl died of blunt injury to the head, face and neck.

Authorities earlier described the tool as a sickle or scythe, but sheriff's Detective Randy Sanders said later Tuesday that authorities aren't completely certain and are trying to determine the type of tool.

The child's body was found Sunday in a plastic container in the garage of the home in Jackson Township where she was living with the uncle and her grandmother, Ward said. The grandmother called 911 Sunday afternoon, saying the girl was dead and covered in blood.

The uncle, Matthew Pierson, has been charged with murder. He told authorities he killed his niece Saturday in the house and described a weapon used to strike her, Sanders said in an affidavit filed in Hillsboro Municipal Court. Pierson also talked about "placing the body in the position in which Jada's body was found," Sanders said.

Authorities declined to comment on a possible motive. A judge set bail at $500,000 at his arraignment Tuesday. Pierson's attorney, J. D. Wagoner, did not return phone calls.

Highland County Prosecutor Anneka Collins declined to comment Tuesday but said more charges were possible. A preliminary hearing was set for Aug. 23.

The sheriff said another man who was in custody earlier for questioning has been released.

Jackson Township is about 60 miles east of Cincinnati.