Officers are offering £1,000 to anyone who can help them locate and charge a man who absconded from a Doncaster prison last week.
Michael Forster, aged 41, from the Gateshead absconded from Hatfield Prison, in Thorne Road at around 1pm on Wednesday, November 26.
He fled the prison with Barry John Henry Lynn, who yesterday (Sunday, November 29) handed himself in to Northumbria police and now remains in police custody.
Officers in both the South Yorkshire and Northumbria force areas are currently looking for Forster.
Police have confirmed that if any information given to Crimestoppers results in those responsible being charged, a cash reward of up to £1000 may be offered.
Anyone who has any information about the whereabouts of Forster is asked to contact police on 101.
Anyone who sees him is urged not to approach him and is asked to ring 999.
Information can also be passed to the independent charity Crimestoppers, anonymously, on 0800 555 111.