Aaron Bremmer, 39, had been serving a 16-year sentence for two counts of rape, four counts of assault by penetration, one count of sexual assault and one count of common assault.
Bremner, who is described as being white, of medium build and around 5ft 9ins tall, lives in Fareham, although officers from Hampshire Constabulary believe he could have travelled to the South Kensington area of London.
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Aaron Bremner (Image: Hampshire Constabulary)
During his trial in 2013, the court heard that Bremner was described by Judge Derwen Hope as “extremely dangerous”.
A spokesperson for Hampshire Constabulary said: “If you see him, then please do not approach him but contact us immediately.
“You can do so by calling 999, quoting the reference 44240546890.
“If you have any information on his whereabouts which may assist our enquiries, then you can contact us by calling 101, and providing the same reference.
“You can also contact Crimestoppers 100 per cent anonymously, by calling 0800 555 111.
“We would also like to remind people that anyone found to be harbouring Bremner, in order to deliberately obstruct our attempts to locate him, may be committing an offence and be liable for arrest themselves.”