Dean Goodwin, 32 and a registered sex offender is described as ‘dangerous’.
Members of the public have been urged not to approach if they see him, but to call 999.
The victim of the assault is recovering with members of her family.
Dozens of police officers have been involved in the search for Goodwin and high visibility patrols are in place around Bournemouth and Poole.
The police helicopter has also been used to try to track him down.
Just call 999: Anyone with information about Dean Goodwin should either call 999 or 0800 056 0154 or 0207 1580011.
Goodwin is described as white, five feet ten inches and of a stocky muscular build.
He has very short hair to the extent that he may appear bald.
He was last seen wearing black jeans, a green top, brown boots and a black jacket, although he may have discarded this clothing.
He has served time for sexually abusing both women and children and is categorised as a “high risk” sex offender.
Goodwin was only released from prison last year after serving 12 years for his offences which happened in the Bournemouth and Poole area.
It is understood that he has been living locally since then, with at least one address being a hostel in Poole.He Detective Inspector Marcus Hester told the Daily Echo: “Officers are continuing to search for Dean Goodwin.
“We need to trace him urgently.
“I would urge any member of the public to contact us immediately if they see him or anyone hiding or acting suspiciously.”
The woman was savagely attacked in a property in Poole one evening last week.
DI Hester of MCIT, Dorset’s Major Crime Team, said: “It was a particularly nasty attack on the young woman.
“She is recovering in the care of her family and being supported by specially trained officers.”
He added: “I am appealing to Mr Goodwin to make contact with us as soon as possible.
“I want to make it clear that anyone found to be helping, harbouring or in any way aiding Dean Goodwin will be arrested.”
Sex offender Goodwin was previously on the run briefly in 2009 after failing to announce himself at a registered hostel in the West Country.
Avon and Somerset issued an alert for him at that time, describing him as ‘potentially dangerous’ and warning he should not be challenged by the public.
He was eventually arrested by Hampshire police on the Isle of Wight after buying a train ticket in Bristol.
This site is part of Newsquest's audited local newspaper network | A Gannett Company
Newsquest Media (Southern) Ltd, Loudwater Mill, Station Road, High Wycombe, Buckinghamshire. HP10 9TY|1350|Registered in England & Wales
This website and associated newspapers adhere to the Independent Press Standards Organisation's Editors' Code of Practice. If you have a complaint about the editorial content which relates to inaccuracy or intrusion, then please contact the editor here. If you are dissatisfied with the response provided you can contact IPSO here