Police are looking for a prisoner who jumped from a private security firm’s van in West Lothian.
Anthony Ferrie, 33, was being taken back to Addiewell jail in a G4S vehicle following a visit to Livingston’s St John’s Hospital.
Ferrie, attacked two G4S guards leaving one unconscious and the other with an arm injury.
Officers are using a helicopter as part of the search.
The escape happened at around 14.15.
Willie Galloway, head of operations for G4S’s custody transport in Scotland, said: “During a prisoner transport movement at approximately 1pm today, a prisoner escaped custody at St John’s Hospital in Livingston.
“Two members of our crew were injured during the incident which left one unconscious and the other with an injury to their arm.
“While they both remain in hospital, their injuries do not at this stage appear to be life threatening and we are supporting them and their families.
“We are assisting Police Scotland’s enquiry to recapture this prisoner and are working with the Scottish Prison Service to understand the events leading up to this escape.”
Ferrie is described as white, 6 foot tall, of slim build and is wearing a blue sweater, jeans and trainers. Ferrie has links to Bellshill, Motherwell and Grangemouth.
If seen, members of the public should not approach him and should contact Police Scotland on 101.
Anyone wishing to provide information anonymously can do so through the charity Crimestoppers on 0800 555 111.
A spokeswoman for the Scottish Prison Service said: “We are aware that an individual has escaped from the custody of G4S while on a hospital escort.
“We are assisting Police Scotland to apprehend them.”