An investigation is under way into a suspected security breach at two Adelaide prisons.
Police are trying to determine if a forged access pass was used by an unauthorised person to gain entry to high-security areas at Yatala and the women's prison.
A person with limited access and possibly a criminal record was found with what may be a doctored pass, 9News understands.
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The incident has raised fears the person accessed unauthorised areas at one or both prisons without an escort.
The South Australia Department for Correctional Services confirmed that an "identification card was confiscated and suspended at the gatehouse at Yatala Labour Prison".
The department said the prisons have "stringent access control measures", including identification checks and biometric registration.
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"Any attempt to breach these stringent controls is treated very seriously," a spokesperson said.
The matter has been referred to SA Police.
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