More than 400 freed sex offenders went on to commit rape in the last three years According to the Daily Mail, 86 of the 769 rapists released from prison in 2010 had served less than half their sentence. A spokesman for charity Rape Crisis told the newspaper: "What these figures demonstrate is that rapists are serial offenders - something we have always believed to be true. "They also demonstrate that rape can be an escalation of a similar offence that the individual has already "got away with" or where the punishment has not acted as a deterrent to further offending." Conservative MP Priti Patel said the Government's priority must be to ensure prolific sex offenders are imprisoned to "keep the public safe." "These are disturbing figures that show too many dangerous criminals are being let off the hook and allowed to reoffend over and over again," she said. A spokesman for the Ministry of Justice said: "Public protection is our priority and we are determined to have the best possible systems in place to supervise offenders in the community. Those who commit such abhorrent crimes will be returned to prison and face a lengthy sentence. In the vast majority of cases, the probation service and police work together successfully to reduce the risk of serious further offending, but unfortunately risk can never be eliminated entirely. Overall, the figures showed hundreds of criminals released from jail early went on to commit further offences while under curfew or wearing electronic tags. Offenders being monitored following release were convicted on 206 serious further offences in 2010 to 2011. In 2009-10, 63 rapes were committed by prior offenders, with 75 the year before.