Crimestoppers charity is offering a reward of up to £5,000 for information that leads to the capture of Jason Sufi, 39, who escaped from prison on 20 February.
Sufi was serving a nine-year sentence for burglary, false imprisonment and robbery at HMP Spring Hill, an open prison in Buckinghamshire.
Other serious offences include stabbing a female police officer when resisting arrest.
Since absconding from prison, he has been linked to a series of aggravated burglaries and a robbery with grievous bodily harm across the UK in Oxfordshire, Kent, Cambridgeshire, Hampshire, Wiltshire and Surrey.
He is described as 5ft 6in (1.68m) tall with olive skin, dark hair and a medium build. Sufi is a high risk to the community and people are asked not to approach him.
Annabelle Goodenough, South East Regional Manager for the charity Crimestoppers, said: “We are appealing to anybody who may know of Jason Sufi’s whereabouts to do the right thing and get in contact with us.
“He has shown he can be violent. We should all be able to live in our homes and walk our streets safely without fear, which is why our charity has put up this reward.
“Please help us to keep our streets safe. If you have any information, however insignificant it may appear, please do the right thing and contact Crimestoppers.
"In over 30 years we have always kept our promise of 100% anonymity to everyone who trusts us with their crime information.
“Remember that your information could help keep someone safe from future harm. Our UK Contact Centre is open 24/7 on 0800 555 111 or you can use our anonymous online form at www.crimestoppers-uk.org.
"No one will know you contacted us, and it could be your information that makes a huge difference.”