Police are searching for convicted murderer James Meehan, who is unlawfully at large from a prison in Co Londonderry.
Meehan, 55, has been serving a life sentence following a murder conviction in 2009.
Police said he failed to return to prison after being on day release from HMP Magilligan on Monday.
Officers are appealing for information to assist in locating Meehan, adding that they encourage him to turn himself in.
A spokeswoman said: “We are appealing to anyone who has seen him, or who knows of his whereabouts, not to approach him directly but to contact police on 101, quoting reference 1251 09/12/24.
“Alternatively, information can also be provided to the independent charity Crimestoppers on 0800 555 111 which is 100% anonymous.
“Police would also appeal directly to James to hand himself in.”
Meehan was found guilty of murdering Londonderry man James McFadden outside his home in 2007.
Mr McFadden died after being attacked outside his Moyolla Drive home after he had attended a wedding reception in Co Donegal.
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