Prisoners freed early under a government programme aimed at reducing overcrowding have committed more than 300 further crimes, figures show.
The early release scheme was introduced last June
The Ministry of Justice said 16,197 offenders - 3,000 of whom had been jailed for violence - were freed in the six months to the end of December.
Other figures show 117 inmates ordered to return to jail had gone on the run.
The Conservatives said the early release scheme had created "unnecessary" victims of crime.
Shadow justice secretary Nick Herbert said the victims had been let down by Labour's incompetence.
"Early release of offenders has put the public at risk, but it has failed to deal with prison overcrowding", Mr Herbert said.
"This early release scheme must be scrapped immediately and sufficient prison places provided so that public safety comes first."
The early release programme was introduced by the government last June. Prisoners serving between four weeks and four years are eligible to be let out of jail on licence, 18 days early.
If they breach the terms of that licence, particularly by committing further crimes, they must be returned to prison to complete the rest of their sentence.
Some categories of prisoner are not eligible for the scheme, including sex offenders, those convicted of serious violent crimes, inmates who have previously escaped from custody, prisoners with no permanent address and youths under 18.