CHICAGO (CBS) — Prosecutors in DeKalb County have said the conviction of a 76-year-old man in the 1957 murder of a 7-year-old girl should be overturned, because newly obtained phone records show he could not possibly have abducted and killed her.

In 2012, Jack D. McCullough was convicted of murder in the death of Maria Ridulph, who disappeared from a street corner in Sycamore, where she and a young friend had been playing on Dec. 3, 1957. Her body was found lying in a field in northwestern Illinois five months later.

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In December 1957, McCullough was a 17-year-old Sycamore resident called John Tessier whose family lived about two blocks from the street corner where Maria was last seen.

McCullough was arrested in 2011 in Seattle, nearly 54 years after Maria’s death. His trial the next year is considered one of the oldest cold cases to go to trial in the U.S. He was convicted and sentenced to life in prison.

Maria Ridulph’s 70-year-old brother, Charles, learned about the development in the case early Friday, via email, on his way to Good Friday services.

“I prayed for forgiveness because of my anger, and I prayed for the Lord to enable me to rejoice that Maria is above this,” Ridulph tells CBS 2’s Brad Edwards.

At the time of McCullough’s arrest, authorities said McCullough had been an initial suspect in the investigation, but the case went cold after he joined the military and changed his name.

DeKalb County State’s Attorney Richard Schmack said “newly discovered evidence” shows it is impossible McCullough was in Sycamore when Maria vanished.

“I know that there are people who will never believe that he is not responsible for the crime. Many of these people are my neighbors in Sycamore. But I cannot allow that to sway me from my sworn duty,” he said.

Schmack said his office has obtained phone records showing McCullough placed a call from a pay phone from the post office in downtown Rockford shortly before 7 p.m. on Dec. 3, 1957.

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Documents filed in the case show Maria disappeared sometime between 6:45 p.m. and 6:55 p.m., and prosecutors said even if she had been abducted as early as 6:30 p.m., McCullough would have had to average more than 100 mph to cover the distance from Sycamore to Rockford by the time he made the call.

Schmack said it took him six months to review 5,000 pages of evidence, but he’s now convinced McCullough did not abduct Maria.

“The only thing we have is to go back to the original FBI reports that show she disappeared at 6:45, and that the person who has been convicted of her abduction and murder was in Rockford at 6:57,” he said.

On Friday, the Illinois State Police issued a statement that says, in part, McCullough’s arrest was the result of a thorough investigation. The police agency also noted his conviction was upheld by a state appellate court.

In light of the new evidence, Schmack said his office will not oppose a defense motion to overturn McCullough’s conviction.

Schmack said a review ordered by the judge in McCullough’s case found several other errors, including:

• A suggestive photo array showed to Maria’s friend, who picked out McCullough’s picture 53 years later from an array of six photos. McCullough’s picture was a snapshot of him wearing a shirt with no coat, and a dark background; while the other five were professional yearbook pictures of young men wearing suit coats, and light backgrounds. McCullough also was the only person in the array who lived in the neighborhood where Maria disappeared.
• Thousands of pages of police reports improperly excluded from the case, pointing to McCullough’s innocence.
• Mistaken testimony from McCullough’s sister that she saw police searching for Maria an hour before she was reported missing.
• False testimony that there was a streetlight on the corner where Maria’s friend saw a man she later identified as McCullough.

“Since McCullough was in Rockford when Kathy Sigman briefly stood on an unlighted corner in Sycamore with Maria’s kidnapper in 1957, her selection in 2010 of a black and white headshot of him as a teenager is clearly an unintentional and tragic mistake on her part,” Schmack said.

McCullough was charged by former DeKalb County State’s Attorney Clay Campbell, who lost to Schmack two months after he was convicted in 2012. Schmack’s decision comes little more than a year after an Illinois Appellate Court panel upheld his conviction.

McCullough was due back in court Tuesday.

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