Michael Lawrence Smith, aged 38, was released erroneously by the Prison Service on Tuesday 7 March and has failed to return to Maghaberry prison.
He has been accused of blasting to death Stephen Carson last year in a house of the Ormeau Road in south Belfast with a shotgun.
Smith, who is currently on remand, had previously applied for High Court bail for this offence.
Police strenuously objected and bail was refused.
Detective Superintendent Kevin Geddes said: “Michael Smith, who is deemed as dangerous, was last seen in the Belfast area at 2 pm on Tuesday 7 March.
“He has an extensive history of violence and I would urge the public not to approach him but contact police immediately.
“I would ask Mr Smith to hand himself in to the authorities without any further delay and ask anyone who knows of his current whereabouts or who has any information to contact police on 999.”