A 33-year-old man on day release from a Suffolk prison is being sought by police after failing to return.
Billy Sullivan, who is serving eight-and-a-half years for wounding and attempting to pervert the course of justice, left Highpoint on 16 December.
Police said he failed to return later that day.
He is 5ft 8in (1.73m) tall, stocky with blue eyes and short, dark, straight hair. He has connections in east London and Essex, police added.
He has a scar near his left eyebrow and speaks with a London accent.
Suffolk Police said Sullivan should not be approached and anyone who may have seen him has been asked to contact the force.