CLEVELAND, Ohio -- A Cleveland man is accused of killing a prostitute 20 years ago after he admitted to investigators that he killed the woman and led the FBI to where he said he buried the woman two decades ago.

Michael Thompson, 64, is charged with aggravated murder.

Federal agents found the body Tuesday on Train and Richner avenues in the city's Stockyard neighborhood, according to court records.

FBI spokeswoman Vicki Anderson said she could confirm the FBI was involved in the excavation but declined to comment further because it's Cleveland police's case.

The Cuyahoga County Medical Examiner's office has not made a positive identification of the woman's remains. Her cause of death has not been determined but her death was ruled a homicide, court records.

Thompson is not in police custody and a warrant was Wednesday issued for his arrest.

Thompson made the confession after falling chronically ill, police said.

Thompson on Aug. 20 called police and asked for officers to come to his home, according to court records.

Third District detectives spoke with Thompson, who told them he killed a prostitute some 20 years ago and buried her body somewhere near Train and West 30th Street, according to court records.

He gave police a written statement and pointed on a map where he buried the woman's body, police reports say.

Officers drove Thompson the site where he pointed out where he buried the body.

Cleveland police, the FBI, Cuyahoga County Sheriffs and the medical examiner's office visited the area Monday and recovered the remains, court records say.

Thompson was convicted in to 18 months in prison for aggravated assault in 1990.

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