Paul Robson, 56, is serving a life sentence for attempted rape and indecent assault.
A “dangerous sex offender” who absconded from an open prison is being searched for by police.
Paul Robson, 56, was reported missing from HMP North Sea Camp in Boston, Lincolnshire, at about 07:00 GMT on Sunday.
He is serving a life sentence for attempted rape and indecent assault.
Det Ch Sup Andy Cox said officers were working on “numerous lines of inquiry” in the hunt for Robson and warned people not to approach him.
“He could be anywhere in the country, and we are really keen to hear from the public with potential sightings so we can take this man off our streets,” he said.
“Robson is a dangerous sex offender and while he presents a particular danger to women and young children, I believe he can cause real harm to anyone he comes across.”
Robson, believed to be originally from Oxford, is described as white and of slim build.
He is bald and was last seen with a long goatee beard.
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