Gwent Police are currently looking for Declan Jones, 22, who failed to return to HMP Prescoed on Friday.
He was convicted of conspiracy to supply class A drugs at Cardiff Crown Court in May 2024.
He is described as around 5ft7" tall, of small build with dark hair, green eyes and is clean shaven.
He has links to Brynmawr, Nantyglo and Ebbw Vale areas.
Police have activated its operational plan with the aim of locating the individual and the prison are co-operating.
Officers have asked you not to approach him and to call on 101 quoting reference 2400420374 if you have any information.
Alternatively you can call Crimestoppers anonymously on 0800 555 111 or visit www.crimestoppers-uk.org.
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