A total of 179 prisoners were freed "in error" in England and Wales between April 2025 and March 2026, or three every week, government figures show.
The Ministry of Justice (MoJ) announced in November that a total of 91 prisoners were released between the start of April 2025 and the end of October 2025.
However, the number for those six months is actually 129, according to the latest available data, with a further 50 inmates freed by mistake since then, the independent report by Dame Lynne Owens said.
The MoJ said releases "in error" can include misplaced warrants for imprisonment or remand, sentence miscalculations, or the result of mistakes by courts or other authorities.
It added: "If the person released is not aware of the error and makes no attempt to evade arrest, then they have committed no additional offence and in that sense, they may not be at fault.
"If it is believed that the situation was manipulated by the prisoner, for example by taking the identity of another person, then this will be classified as an escape, and not a release in error."
'Broken system' blamed
Responding to the report, published on Wednesday, Justice Secretary David Lammy called the figure "unacceptable", blaming a "broken system caused by 14 years of underinvestment and overcrowding in our prisons and courts".
Such a system "cannot be fixed overnight," he warned, while saying his department is "rolling out biometrics, a new Justice ID and up to £82 million to bear down on these errors and keep the public safe after years of chaos.
"£20 million of this will be used this year to digitise the archaic paper-based processes we inherited, as well as putting in more checks and more staff in place to stop these mistakes before they happen."
As well as creating digital identities for prisoners, ministers are planning to use fingerprints and facial scans to reduce the number of mistakes.
Shadow Justice Secretary, Nick Timothy criticised Mr Lammy, saying in a statement the justice secretary "has finally admitted it. 179 prisoners let out by mistake last year. 441 in total under Labour - the highest two years on record. For months he hid the numbers and now he's buried them in a written statement.
"What happened to the 'strongest ever checks'?"
Manhunt for migrant sex offender Hadush Kebatu
Pressure mounted on Mr Lammy last year following a series of high-profile manhunts, most notably for migrant sex offender Hadush Kebatu.
The Ethiopian was jailed for 12 months in September after being convicted of sexually assaulting a 14-year-old girl and a woman in Epping, where he was staying, shortly after his arrival in the UK.
The case of Kebatu, who has since been deported, sparked anti-immigration protests in the Essex town centred on The Bell Hotel, where he was staying.
Ketabu told Sky News he tried to hand himself back in to police after being wrongly released from HMP Chelmsford in October but was ignored by officers before being recaptured following a two-day manhunt costing police £150,000.
In November, Sky's national correspondent, Tom Parmenter and colleague Josh Masters helped track down Algerian Brahim Kaddour-Cherif, who spent more than a week on the run after being mistakenly released from HMP Wandsworth.
Convicted fraudster William Smith, who was also released in error by staff at the jail around the same time, turned himself in following a three-day manhunt.
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Previous high-profile manhunts
William Fernandez, who was awaiting trial for sexual assault, was released from HMP Wormwood by error in March 2021. He then went on to rape a 16-year-old girl and sexually assault a young woman.
In December 2019, the Prison and Probation Service apologised after serial rapist Joseph McCann was freed to commit a series of sex attacks on women and children.
In July 2017, an inmate who was released from prison just months into a nine-year sentence due to a "clerical error" was arrested after weeks on the run.
The number of blunders had fallen compared to the previous year, the government said.
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(c) Sky News 2026: 179 prisoners freed 'in error' in England and Wales in single year

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