A disc, holding details of serious crimes abroad, lay unchecked for a year
An inquiry has found "significant shortcomings" in the Crown Prosecution Service's handling of DNA data linked to serious crimes abroad.
Dutch police sent a disc, containing 2,159 DNA profiles from crime scenes, to the CPS in January 2007, so it could be checked against the UK's database.
But the checks did not start until February this year, since when 15 matches have been found.
Attorney General Baroness Scotland said the delay had been "regrettable".
In the year before the blunder was uncovered, at least 11 of the individuals wanted for serious crimes in the Netherlands, including rape and murder, went on to commit offences in the UK, including assault and non-payment of fines.
An operation involving police and the Serious Organised Crime Agency was launched to try to locate the 15 individuals found to have been in the UK.
The review was carried out by CPS chief executive Peter Lewis.
His report said the data was unexpectedly sent to the CPS, not the police, by ordinary business post and was not addressed to a particular department or individual.
The correct lawyer received it in April 2007 but then began a long and unexpected period of absence, the report said.
Although the lawyer returned to work in October, the disc was not collected until 11 January this year.
The inquiry found no evidence that the disc had been copied or ever left the building.
Instead, it blamed individual failings and said they were now facing disciplinary action.
The most serious weakness in the initiative was "the extremely regrettable failure of CPS personnel to deal appropriately and expeditiously with the disk of DNA profiles unexpectedly entrusted to the CPS", he said.
"For this failure, and the delay to the process caused by it, the CPS apologises unreservedly."
He said as well as staff disciplinary procedures, management action and internal changes had begun which should prevent the same thing happening again.
Baroness Scotland said the inquiry showed the value of exchanges of data which could lead to the prosecution of criminals, who would not be bought to justice otherwise, and the establishment of a DNA database.
In a written statement, she said: "However, the report reveals significant shortcomings in the way in which this process was planned and implemented.
"There was a highly regrettable delay to the process while the disc was in the possession of the CPS."
One of a number of recommendations, which have been accepted, was that arrangements for exchange should be subject to ministerial approval in the future.