The Serious Fraud Office (SFO) said that instead of returning thousands of pages of evidence to 59 different sources, it sent the entire batch of material to a single recipient.
The office said it had already contacted the 59 people involved and that it is "working to contact any others who may have been affected".
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The family of two little girls who were left paralysed following a crash say they will never forgive the driver who caused the collision.
A driver who paralysed two little girls in a road rage crash was jailed for 4 and a half years.
A driver who left two sisters paralysed after his 4x4 smashed into their family car during a road rage chase, has been jailed.