SYCAMORE, Ill. (CBS) — Prosecutors and investigators are to hold a news conference in Sycamore Tuesday afternoon to release more information about their case against a defendant in a 54-year-old murder case.

As WBBM Newsradio 780’s Regine Schlesinger reports, former police officer Jack Daniel McCullough, 71, is charged with kidnapping and murdering Maria Ridulph, 7, as she played in the snow near her Sycamore home in 1957. McCullough now lives in Seattle.

LISTEN: Newsradio 780’s Regine Schlesinger reports

Prosecutors on Tuesday will discuss the some of the evidence that led to McCullough’s arrest more than half a century after the crime.

He has pleaded not guilty to charges of being a fugitive, as authorities attempt to have him returned to Illinois to face murder charges.

In an interview with the Associated Press last week, Ridulph stuck to the same alibi he gave when first questioned by investigators after the murder, when he was 18 and going by the name John Tessier. He said he had traveled to Chicago on the day of the murder to undergo military medical exams before enlisting in the Air Force.

“I have an iron-clad alibi,” he said. “I did not commit a murder.”

But a former girlfriend of McCullough recently came across an unused train ticket hidden behind a framed photograph he gave her. That was when police zeroed in on him again as Maria’s possible killer.

Maria disappeared on Dec. 3, 1957.

The girl’s playmate, Kathy Chapman, now 61 and living in St. Charles, Ill., has said she and Maria were at a street corner when a teenage boy she knew as “Johnny” offered them a piggyback ride. Chapman said she ran home to get mittens and returned to find Maria and the boy gone.

Maria’s remains were found in April 1958. They were discovered in April 1958 in Jo Daviess County, about 120 miles away in the northwest corner of Illinois.

Chapman has said police never showed her a photo of McCullough after Maria went missing until last September. She said she identified a photo of a teenage McCullough as the “Johnny” who approached her and Maria the night her friend vanished.

Meanwhile, a police affidavit in the case raises other allegations against McCullough, saying he had a history of molesting girls.

One young witness told agents in 1957 that he had sexually abused her on numerous occasions, and in the early 1980s he lost his job with the Milton police department in Washington state after he was accused of having sexual abuse with a runaway in her early teens. He pleaded guilty in 1983 to unlawfully communicating with a minor.

McCullough declined to discuss those topics with the AP.

The news conference Tuesday will be held at the DeKalb County Legislative Center, at 200 N. Main St. in Sycamore. DeKalb County State’s Attorney Clay Campbell, Sycamore police and the FBI will be present.

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