Almost 40 people were let out of prison by mistake under Labour's controversial early release scheme, the Ministry of Justice has admitted.

One MoJ source said some 37 criminals were released erroneously on September 10 becuase their offences had been recorded incorrectly under now-repealed legislation.

As a result, the cases were not flagged for exemptions meant to stop criminals guilty of certain offences from being released.

Five prisoners are still on the loose, but "most" have been brought back into custody, the source said.

A Ministry of Justice spokesman said: "Public safety is our first priority. That is why we took decisive action to fix the broken prison system we inherited and keep the most dangerous offenders locked up.

"This included blocking the early release of domestic abuse offences such as stalking and controlling behaviour.

"We are working with the police to urgently return a very small number of offenders - who were charged incorrectly and sentenced under repealed legislation - to custody.

"The convictions remain valid with offenders monitored since their release and will soon be back behind bars."

Some 1,700 criminals had been handed their freedom early by Labour in a controversial move meant to ease up a nationwide overcrowding crisis stemming back years.

The MoJ had said the crisis had effectively pushed British prisons to the "point of collapse" - and new Justice Secretary Shabana Mahmood's solution was to temporarily slash the amount of time inmates must spend of their sentences in jail by a fifth.

And despite today's news of the blunder, a similar number are set to be released next month.