Police in Salisbury believe 30 year old Michal Kisiel's escape from prison was pre-planned.
He escaped from guards at Salisbury District Hospital around 7pm yesterday while being treated for a head wound.
Extensive searches were carried out last night with police dogs, a helicopter and drones.
Police are exploring a number of leads, including looking at transport routes out of Salisbury.
House to house enquiries are being conducted in the area surrounding the hospital.
Anyone with any information on the location of Kisiel is urged to come forward.
CID in Salisbury have taken over the investigation and we are working closely with the Ministry of Justice and local policing teams."
Public safety is our priority and we are doing everything we can to find this man. Extra hi visibility reassurance patrols will be ongoing in the local area. We will keep the community updated but if anyone has concerns I would encourage them to speak to their local Community Policing Team officers via 101."
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