Ian Acheson, a former government adviser on extremism in jails, said: “Emergency mass release of prisoners, while necessary, only resulted in a transfer of risk from overcrowded prisons to under-policed communities, with a probation service already on its knees.

“It seems likely we will be here again soon with unsuitable offenders released earlier than a judge directed with a higher likelihood of harm in the community. The only viable response is ‘safety first’, with recidivists not properly prepared for release.”