Police are searching for a 22 year-old man who has fled Prescoed Prison, near Usk.
William Philip Goldie is described as being 6ft tall and of slight build. He has short brown hair and blue eyes.
In 2009, Goldie was convicted of possession of controlled drugs with intent to supply and sentenced to 30 months in prison.
Police say he has links to the Gloucester area, and have asked anyone with information to contact them on 01633838111, or Crimestoppers on 0800 5551111.