Police have launched a manhunt for a criminal who absconded from prison in Buckinghamshire. Thames Valley Police has warned the public not to approach Mahad Elmi, 27, who left HMP Springhill "some time overnight" between Christmas Day and Boxing Day.

Elmi is now considered to be "unlawfully at large", with no authority or lawful license to be in the community. He was described as a black man, around 5ft 8ins tall, of medium build with medium length black hair, a beard and brown eyes. Police said he was known to have links to south-west London.

He had been housed in the Category D men's open resettlement prison in the village of Grendon Underwood, Buckinghamshire.

In resettlement prisons, which focus on preparing inmates for release, prisoners can be granted day release to go to work, or maintain family ties. Around 330 prisoners live at Springhill, most of whom share a cell.

Detective Sergeant Matthew French, of Buckinghamshire's Priority Crime Team, said: "We are appealing for the help of the public to trace Mahad Elmi, who is unlawfully at large after leaving and not returning to HMP Springhill.

"If you see Elmi, do not approach him and call 999 instead. If you have any information as to where Elmi may be, please call 101 or make a report online, quoting reference number 43250653119."

Police have also launched an urgent manhunt in relation to an open prison in Derbyshire. The public was warned not to approach Ethan Black, who climbed a fence and escaped from HMP Sudbury at around 8.15pm on Wednesday, December 17.