A man serving a life sentence for the 1990 murder of a 4-year-old girl was freed from prison Thursday afternoon after prosecutors submitted a document to the Tokyo High Court earlier in the day approving the move based on recent DNA tests that highly likely prove his innocence.

Speaking at a press conference following his release from Chiba Prison in Chiba, Toshikazu Sugaya, 62, made no attempt to conceal his anger. He was arrested in 1991.

"I'll never forgive the police and prosecutors who [handled the case] at the time, even if they say 'We made a mistake,'" Sugaya said. "I want them to give me back my life."

He is expected to be retried in a few months on suspicion of kidnapping and murdering the girl in Ashikaga, Tochigi Prefecture, and likely will be confirmed innocent.

The Supreme Public Prosecutors Office has set up a task force to check evidence and records related to the case in an attempt to learn how this error occurred.

According to the Justice Ministry, this is the first time that prosecutors have asked for a convict's release ahead of a retrial. The Supreme Court acknowledged a DNA test as admissible evidence for the first time in this case.

As a result, this case could potentially influence the convictions of other criminal trials that were based on early DNA tests, while calling into question investigative methods and court rulings.

Sugaya's defense counsel filed an appeal last year after his petition for a retrial was dismissed by the Utsunomiya District Court in Tochigi Prefecture. As part of the appeal, forensic scientists - recommended by both the prosecutors and the defense counsel - conducted DNA tests on dried body fluids found on the victim's clothing.

The results of the new tests were compiled last month, with doctors from both sides saying it was highly likely that the DNA was not Sugaya's.

The Tokyo High Public Prosecutors Office later carried out DNA tests on the investigators who originally probed the case, suspecting that one of them could have come into contact with the girl's clothing. However, the tests proved negative, the prosecutors said.

The prosecutors concluded that the fresh DNA tests were "strong enough evidence to judge that [Sugaya] is innocent."

In the document submitted to the Tokyo High Court, the prosecutors consented to a retrial for Sugaya, saying they want the court to make an appropriate decision on the start of the retrial.

If the Tokyo High Court approves the launch of a retrial, it will be held at the Utsunomiya District Court.

Though unusual, Sugaya's mid-sentence release is based on the Criminal Procedure Code, which stipulates that prosecutors can suspend a sentence currently being served.

The 4-year-old girl was found dead on a riverbank the day after she went missing from a pachinko parlor on May 12, 1990. The girl's undershirt was later recovered from the riverbed and the National Research Institute of Police Science, under the National Police Agency, concluded that the DNA detected on the shirt matched that of Sugaya's.

In December 1991, the Tochigi prefectural police arrested Sugaya after he confessed to killing the girl when informed about the DNA match. He later confessed to the murders of two more female children, but these two cases were not prosecuted due to insufficient evidence.

During his first trial at the local district court, Sugaya withdrew his confession and pleaded not guilty. However, both the district court and the Tokyo high court convicted him, concluding that the results of the DNA tests and his original confession were credible.

In 2000, the Supreme Court dismissed Sugaya's appeal and his life sentence was finalised.